0:00:03 > 0:00:05These are the Tepuis of Venezuela...
0:00:08 > 0:00:10..ancient towers of rock...
0:00:12 > 0:00:15..isolated refuges for rare plants and animals...
0:00:17 > 0:00:19..lost worlds,
0:00:19 > 0:00:23cut off by sheer-sided cliffs from the jungle below.
0:00:23 > 0:00:24'My name is Steve Backshall.'
0:00:24 > 0:00:26Come on!
0:00:26 > 0:00:28'I'm a naturalist and adventurer.'
0:00:28 > 0:00:32Oh, wow!
0:00:32 > 0:00:36'And to me, nowhere says adventure more than this place.'
0:00:38 > 0:00:41'So I'm leading a team of top climbers,
0:00:41 > 0:00:45'expedition professionals, and film-makers,
0:00:45 > 0:00:50'on a month long expedition to explore these islands in the sky.'
0:00:50 > 0:00:51Wow!
0:00:51 > 0:00:52'To search for wild life...'
0:00:52 > 0:00:55Monster!
0:00:55 > 0:00:58'..and to understand how they were formed.
0:00:59 > 0:01:03'We're going inside a Tepui to explore a vast, unchartered cave.'
0:01:08 > 0:01:09I don't like this at all.
0:01:11 > 0:01:15'And taking an abseil alongside the highest waterfall in the world.'
0:01:15 > 0:01:20Whoa, that is out of this world!
0:01:24 > 0:01:26But at the end of week two,
0:01:26 > 0:01:29we still haven't completed our first objective -
0:01:29 > 0:01:32to climb an unclimbed Tepui and explore its summit.
0:01:37 > 0:01:40'We've spent four days tackling this monster cliff face.'
0:01:40 > 0:01:41Oh!
0:01:46 > 0:01:48Oh, it's really hard!
0:01:49 > 0:01:52'And now we're running out of time.'
0:01:52 > 0:01:53HE BREATHES HEAVILY
0:02:07 > 0:02:11Day five of the climb and we wake on a precarious ledge,
0:02:11 > 0:02:14halfway up the mountain.
0:02:15 > 0:02:19What a difference a day makes.
0:02:19 > 0:02:23It's the first time we've woken up, we've not been inside a cloud.
0:02:23 > 0:02:28I can actually see the mountains and blue sky.
0:02:30 > 0:02:32What do you reckon? Do you think our luck's changing?
0:02:32 > 0:02:34Fingers crossed.
0:02:34 > 0:02:37It would be nice after yesterday, wouldn't it?
0:02:39 > 0:02:41The previous day, our attempt to become
0:02:41 > 0:02:44the first people to climb this vertical rock face
0:02:44 > 0:02:46almost ended in disaster.
0:02:46 > 0:02:49The birds are all coming into roost.
0:02:49 > 0:02:52There's a big storm coming and they know it.
0:02:52 > 0:02:53What a storm.
0:02:53 > 0:02:57It left us clinging to the cliff, and then came the rock fall.
0:02:57 > 0:02:58No, no, no, no!
0:02:59 > 0:03:01Head, head!
0:03:04 > 0:03:07We've got to get off this thing. Someone's going to die.
0:03:07 > 0:03:09'You could taste the fear.'
0:03:09 > 0:03:14- It's just really dangerous, isn't it, up here?- Phew.
0:03:14 > 0:03:20It's only a mountain, you know, nothing is worth risking this for.
0:03:22 > 0:03:25I'll tell you what, after yesterday I was...
0:03:25 > 0:03:29I was all about just getting the hell off this mountain,
0:03:29 > 0:03:35but now I kind of feel we should keep going. What about you?
0:03:35 > 0:03:39- Yeah.- You do? - Yeah, give it a bash.
0:03:39 > 0:03:42Well, we've come an awful long way.
0:03:42 > 0:03:44It would be a shame to give up so easy.
0:03:47 > 0:03:50Time to make one last attempt to get to the top.
0:03:57 > 0:04:00The climbers set off from the ledge to establish a route.
0:04:05 > 0:04:09Brit John Arran, and Venezuelan Ivan Calderon,
0:04:09 > 0:04:13are amongst the world's best Tepui climbers.
0:04:13 > 0:04:15Meanwhile, halfway up the cliff face,
0:04:15 > 0:04:19team medic Aldo Kane and support climber Fuko Pisani
0:04:19 > 0:04:24construct a quarter ledge camp in preparation for the night ahead.
0:04:24 > 0:04:27Whilst below, cameraman Keith Partridge and I wait on the ledge
0:04:27 > 0:04:28ready to follow up the cliff face,
0:04:28 > 0:04:31once the climbers reach a safe position.
0:04:34 > 0:04:37But this waiting game doesn't suit me.
0:04:37 > 0:04:40Too much time to brood on potential disaster.
0:04:40 > 0:04:43We've now been on this thing for five days.
0:04:43 > 0:04:47That was supposed to be how long we would take to summit, and we're
0:04:47 > 0:04:51only a little way past halfway,
0:04:51 > 0:04:54so John and Ivan have pushed on ahead.
0:04:54 > 0:04:57They're trying to cover some serious distance without me
0:04:57 > 0:05:00slowing them down, and without the camera slowing them down,
0:05:00 > 0:05:03and I really hope that they're safe up there.
0:05:08 > 0:05:10But the omens aren't good.
0:05:17 > 0:05:19'Another rock fall.'
0:05:19 > 0:05:20Aldo, are you OK?
0:05:22 > 0:05:23Aldo?
0:05:31 > 0:05:33Keith to Aldo, do you read? Over.
0:05:35 > 0:05:37'Aldo. Send.'
0:05:37 > 0:05:40OK. No, just huge lumps of rock came down.
0:05:40 > 0:05:42Just making sure you're all OK up there.
0:05:42 > 0:05:45'Yeah, I'm not sure where that came from. Over.'
0:05:49 > 0:05:53High above, John and Ivan are actually making good progress.
0:05:58 > 0:06:01Then, around mid-day, they hit a problem.
0:06:02 > 0:06:05Blocking their way is a band, or strata, of rock
0:06:05 > 0:06:07that looks close to un-climbable.
0:06:08 > 0:06:10What do you think, Ivan?
0:06:26 > 0:06:27Usually, the quartzite sandstone
0:06:27 > 0:06:30that makes up these cliffs is bullet-hard,
0:06:30 > 0:06:34but this band is different, heavily fractured.
0:06:34 > 0:06:35Ivan decides to keep going.
0:06:35 > 0:06:39There's no alternative if we're going to make the summit,
0:06:39 > 0:06:40but it's a gamble.
0:06:40 > 0:06:42He's climbing at the very limit.
0:06:49 > 0:06:50Sitting on my ledge, I'm unaware of
0:06:50 > 0:06:54the intensifying drama 100 metres above me.
0:06:54 > 0:06:56Until...
0:06:56 > 0:06:57YELLING
0:07:00 > 0:07:02I think that might be us.
0:07:02 > 0:07:05Just quickly, just check.
0:07:05 > 0:07:07'Steve, this is John, over.'
0:07:07 > 0:07:08John, go ahead.
0:07:10 > 0:07:14'Hi, Steve. We've had a bit of an incident up here.
0:07:14 > 0:07:18'Ivan took a big fall, about a 50 foot fall.
0:07:18 > 0:07:19'I got slammed into the rocks,
0:07:19 > 0:07:24'and I've got a fairly nasty cut on my chin and lower lip. Over.'
0:07:25 > 0:07:30Our cameras just missed Ivan's massive fall.
0:07:30 > 0:07:34Here he is moments later climbing back up the anchor rope,
0:07:34 > 0:07:37and this is where he fell from.
0:07:37 > 0:07:40Incredibly, Ivan isn't really hurt at all.
0:07:42 > 0:07:46John, what do you think? Over.
0:07:46 > 0:07:49'Well, we certainly can't go the way we just tried,
0:07:49 > 0:07:51'and that looked to be the easiest way.
0:07:51 > 0:07:54'The only other alternative would be
0:07:54 > 0:07:56'a fairly severe traverse left and right
0:07:56 > 0:08:00'but it would take four or five days. Over.'
0:08:00 > 0:08:04'But we don't have supplies for another four or five days.
0:08:04 > 0:08:07'It's time to face reality.'
0:08:07 > 0:08:10The Tepui has defeated us.
0:08:10 > 0:08:13That sounds like decision time, to me.
0:08:13 > 0:08:17First of all you need to get back down to here so Aldo can treat you,
0:08:17 > 0:08:22possibly put some stitches in you, and secondly, we retreat.
0:08:25 > 0:08:26That's it, then.
0:08:30 > 0:08:32This is as high as we get.
0:08:34 > 0:08:36Our climb is over.
0:08:40 > 0:08:42John and Ivan retreat to where
0:08:42 > 0:08:45expedition medic Aldo is waiting below.
0:08:45 > 0:08:47Worst nightmare, really.
0:08:47 > 0:08:51Un-climbable rock, effectively.
0:08:51 > 0:08:53Never seen that on a Tepui before.
0:08:53 > 0:08:56Not the same kind, anyway.
0:08:56 > 0:09:03Just about ten metres of completely green, shattered rock.
0:09:03 > 0:09:04So what happened with Ivan?
0:09:04 > 0:09:06He was trying to head through this.
0:09:06 > 0:09:08He was putting little pegs in,
0:09:10 > 0:09:13and he was getting further and further away,
0:09:13 > 0:09:15and eventually something just ripped,
0:09:15 > 0:09:18- and every single piece he put in...- Every single bit!
0:09:18 > 0:09:20..all just went ping, ping, ping, ping.
0:09:20 > 0:09:22Big block came straight out.
0:09:22 > 0:09:25- How far do you think he fell? - About 50 feet.
0:09:25 > 0:09:28Went straight down onto... onto the anchor.
0:09:28 > 0:09:29Thankfully we had a good anchor in.
0:09:29 > 0:09:32- But he's not injured? He hasn't... - He's not injured at all.
0:09:32 > 0:09:35He's got tiny cuts on his... on his hand, but it's nothing.
0:09:35 > 0:09:38- Sounds like that was incredibly lucky.- Yeah.
0:09:40 > 0:09:42I'm desperate to find out how the boys are,
0:09:42 > 0:09:47so I climb the fixed rope as quick as I can.
0:09:50 > 0:09:54- Are you all right, mate, are you OK? - Yeah, yeah, I... I'm OK.
0:09:54 > 0:09:56That... that is a big, big fall to take.
0:09:56 > 0:09:59Yeah, yeah, it was scary but every...
0:09:59 > 0:10:01everything happened so fast.
0:10:01 > 0:10:05It's a rush of adrenaline, so you... After the fall,
0:10:05 > 0:10:09you feel like really, really light, you know, like, "Phew",
0:10:09 > 0:10:12I don't say... I don't know if, if, if I can say that,
0:10:12 > 0:10:15but it's like an orgasm, yeah.
0:10:15 > 0:10:16It's like an orgasm?
0:10:16 > 0:10:18Yeah, something like that.
0:10:18 > 0:10:21Mate, you're doing one of those things wrong.
0:10:21 > 0:10:22I'm not sure what it is.
0:10:23 > 0:10:27No, but I think we took the right decision,
0:10:27 > 0:10:29- because I think... - It's the only decision.
0:10:29 > 0:10:31- It is the only decision.- Yeah.
0:10:37 > 0:10:39We all hate to be beaten.
0:10:39 > 0:10:42Abandoning the climb feels like a punch in the guts...
0:10:44 > 0:10:47..but pushing on further would be madness.
0:10:47 > 0:10:50All I can do is put a brave face on it.
0:10:53 > 0:10:57I have to say, being here in this extraordinary,
0:10:57 > 0:11:00almost otherworldly light,
0:11:00 > 0:11:02with the swifts and the swallows circling around my ears,
0:11:02 > 0:11:05it is one of the most extraordinary places I've ever been.
0:11:05 > 0:11:08And we know for a fact that we are the first people ever to be here,
0:11:08 > 0:11:11so this doesn't feel like failure, far from it.
0:11:11 > 0:11:14But I came here to explore the lost world
0:11:14 > 0:11:18on the very top of a Tepui, and we can still do that.
0:11:18 > 0:11:22That huge looming shape in the background is Auyan Tepui.
0:11:22 > 0:11:23It's one of the very biggest,
0:11:23 > 0:11:25and on the summit is an environment
0:11:25 > 0:11:27that's unlike anywhere else on Earth,
0:11:27 > 0:11:31and we can get there without having to climb.
0:11:31 > 0:11:33That is just fine by me.
0:11:45 > 0:11:49Leaving the climbing team behind, team medic Aldo,
0:11:49 > 0:11:51the film crew and I take to the air.
0:11:53 > 0:11:57Our destination is the huge Auyan Tepui.
0:12:00 > 0:12:04Recently a cave system has been discovered inside the Tepui.
0:12:06 > 0:12:10Our objective is to explore this cave...
0:12:10 > 0:12:13treading where no-one's been before...
0:12:14 > 0:12:17..and shedding new light on how the Tepuis are formed.
0:12:20 > 0:12:22But before that, I have unfinished business.
0:12:24 > 0:12:27I may not have been able to climb onto the summit of a Tepui,
0:12:27 > 0:12:30but I'm still desperate to explore one.
0:12:33 > 0:12:35This is actually a much denser,
0:12:35 > 0:12:37more developed forest than I was expecting
0:12:37 > 0:12:41on the top of this Tepui, and that river is incredible.
0:12:42 > 0:12:46Oh, wow!
0:12:48 > 0:12:51No way!
0:12:52 > 0:12:55HE LAUGHS
0:12:55 > 0:12:56Woohoo!
0:13:02 > 0:13:05'But I need more than an aerial tour...
0:13:06 > 0:13:10'..so the pilot picks out a suitably remote spot
0:13:10 > 0:13:13'to give me a few hours to look around.'
0:13:13 > 0:13:15I think he's taking us down to the top of the waterfall.
0:13:15 > 0:13:18If he tries to land there he's crazy.
0:13:28 > 0:13:32Oh, my God. Ha, ha, ha, ha!
0:13:34 > 0:13:37I really do feel like I've just
0:13:37 > 0:13:40beamed down from a spaceship onto an alien planet.
0:13:43 > 0:13:46Look at these totem poles, almost.
0:13:46 > 0:13:48I've never seen anything like it.
0:13:56 > 0:13:58At last, the summit of a Tepui.
0:13:59 > 0:14:01We may have cheated a little to get here,
0:14:01 > 0:14:04but I think we've earned it.
0:14:10 > 0:14:12I've got a few precious hours to explore,
0:14:12 > 0:14:17and hopefully find some of the life that inhabits this strange place.
0:14:17 > 0:14:19The elevation and the vertical rock walls
0:14:19 > 0:14:21are a really efficient barrier to life,
0:14:21 > 0:14:24but clearly plants and animals have found their way up here.
0:14:24 > 0:14:28Whether they climb, get dropped or borne on the wind,
0:14:28 > 0:14:30very few of them are going to survive.
0:14:30 > 0:14:33The hardy few that do, will adapt to the conditions here,
0:14:33 > 0:14:36and over millennia, some will turn into new species.
0:14:36 > 0:14:38And then they're going to be trapped up here
0:14:38 > 0:14:41exactly the same as if they were on islands.
0:14:44 > 0:14:46Oh, I've got something!
0:14:47 > 0:14:49Lovely.
0:14:50 > 0:14:53There's a rather charming little black and white spotted weevil
0:14:53 > 0:14:55wandering over this plant.
0:14:55 > 0:14:58This one's flightless and I haven't seen them on the savanna below.
0:14:58 > 0:15:01It's almost certainly a Tepui-top specialist.
0:15:03 > 0:15:07This is one of the reasons why life is so challenging up here.
0:15:09 > 0:15:14On the Tepui tops, it can rain as much as nine metres in a year,
0:15:14 > 0:15:17and that just washes away all the topsoil,
0:15:17 > 0:15:20and all you're left with is sand.
0:15:20 > 0:15:24These Tepui tops are sometimes known as being rain deserts,
0:15:24 > 0:15:28and so the plants have to find other ways of gaining nutrients.
0:15:32 > 0:15:36And a short while later, I find a particularly unusual example
0:15:36 > 0:15:38of how those nutrients can be produced.
0:15:43 > 0:15:44Look at that. Beauty!
0:15:47 > 0:15:49This is the Tepui tree frog.
0:15:49 > 0:15:52It's only found on the summits of mountains like this.
0:15:52 > 0:15:54Though it's very similar in form
0:15:54 > 0:15:57to all the other tree frogs found in the tropics,
0:15:57 > 0:16:02this one here lives inside these plants. They're called Brocchinia.
0:16:02 > 0:16:06The leaves are clasped together into a vase,
0:16:06 > 0:16:07and water collects inside them.
0:16:07 > 0:16:11They will function a little bit like a pitcher plant, and catch insects,
0:16:11 > 0:16:16but they also gain nutrients from these tiny frogs.
0:16:16 > 0:16:20The frogs will sit here on the rim catching insect prey,
0:16:20 > 0:16:23and then as the frogs excrete waste material,
0:16:23 > 0:16:26it drops down into the plant and helps them to grow.
0:16:27 > 0:16:29So there's kind of a symbiosis,
0:16:29 > 0:16:33a mutual relationship going on between the frog and the plant.
0:16:35 > 0:16:39There's never enough time for a place like this.
0:16:39 > 0:16:41I've barely scratched the surface.
0:16:41 > 0:16:43But these few short hours
0:16:43 > 0:16:47have made me even more curious about how the Tepuis are formed.
0:16:49 > 0:16:52For now that's going to have to wait.
0:16:52 > 0:16:54The cave beckons.
0:16:54 > 0:16:57And for that we'll need the help of a specialist caving team.
0:17:34 > 0:17:36THUNDER RUMBLES
0:17:37 > 0:17:39Does that sound like thunder?
0:17:39 > 0:17:41Yeah, thunder, yes.
0:17:41 > 0:17:42So we have a storm coming in.
0:17:42 > 0:17:46Our expedition has been plagued by the early arrival of the rains.
0:17:56 > 0:17:57That is proper rain.
0:17:57 > 0:18:00The only escape is inside the tents.
0:18:00 > 0:18:03But things could be worse.
0:18:03 > 0:18:04The caving team are Italian,
0:18:04 > 0:18:07and they're in charge of catering.
0:18:07 > 0:18:08Look at this!
0:18:08 > 0:18:12At least we're in the right tent where someone's cooking.
0:18:12 > 0:18:14I don't eat this well at home!
0:18:14 > 0:18:17- So we have some good vino to go with this?- Yeah.
0:18:17 > 0:18:19Maybe a nice Chianti?
0:18:19 > 0:18:21ALL: Sangiovese!
0:18:21 > 0:18:23Don't be ridiculous!
0:18:23 > 0:18:26- From Italy.- I love travelling with Italians!
0:18:26 > 0:18:28To celebrate the new exploration!
0:18:28 > 0:18:31What are we celebrating? We're sat in a tent in the pouring rain.
0:18:31 > 0:18:33We are here on the Tepui!
0:18:35 > 0:18:39This wine-loving Italian is Francesco Saro.
0:18:39 > 0:18:41When he's not sipping the good stuff,
0:18:41 > 0:18:43he's the expedition leader,
0:18:43 > 0:18:46and the man who discovered the cave.
0:18:46 > 0:18:50It's a beautiful place. Outside, now, it's a bit hard but...
0:18:57 > 0:19:00Someone teach these guys how to open a bottle of wine!
0:19:10 > 0:19:13ALL: Hooray!
0:19:25 > 0:19:29When we wake up, it's actually dry for a change,
0:19:29 > 0:19:33and we're not the only ones enjoying the sun.
0:19:33 > 0:19:36We have ourselves a visitor.
0:19:36 > 0:19:37It's a possum.
0:19:37 > 0:19:41It's got a long naked, almost rodent-like tail,
0:19:41 > 0:19:45white face with dark markings but actually it's a marsupial,
0:19:45 > 0:19:48believe it or not. It does raise its young in a pouch,
0:19:48 > 0:19:52and it's been going round the outside of our tent.
0:19:52 > 0:19:55That's surprisingly bold, considering we're all here,
0:19:55 > 0:19:56all making loads of noise,
0:19:56 > 0:20:01but I guess any food is going to be really welcome.
0:20:01 > 0:20:04I really didn't expect to see any mammals on top of Auyan Tepui,
0:20:04 > 0:20:07I have to admit. This is a very, very nice surprise
0:20:07 > 0:20:08and actually quite a treat.
0:20:13 > 0:20:14Time to go caving,
0:20:14 > 0:20:18which is just as well because the weather's closing in again.
0:20:27 > 0:20:30It's an atmospheric descent through the mist,
0:20:30 > 0:20:34into an enormous ravine filled with colossal boulders.
0:20:36 > 0:20:40Until recently, no-one was looking for caves inside Tepuis.
0:20:40 > 0:20:42It's the wrong kind of rock,
0:20:44 > 0:20:47which made Francesco's discovery all the more exciting.
0:20:49 > 0:20:52It was this dramatic gorge that led him to the cave.
0:20:57 > 0:20:59- We were searching for collapses. - Yeah.
0:20:59 > 0:21:01- It means that there is a void. - Uh-huh.
0:21:01 > 0:21:04And then we were studying satellite images,
0:21:04 > 0:21:07and we found this one, which was very big,
0:21:07 > 0:21:09- you can see it's a huge collapse. - Yeah.
0:21:09 > 0:21:14- Can form only if there is a cave below.- Uh-huh.
0:21:14 > 0:21:18The cave Francesco and his team discovered is vast.
0:21:18 > 0:21:20How big, no-one yet knows.
0:21:22 > 0:21:26So far they've found over 20km of passage,
0:21:26 > 0:21:29but our job is to push even deeper into the cave.
0:21:31 > 0:21:33It's more than just exploration, though.
0:21:33 > 0:21:36Going inside a Tepui gives us the chance to understand what
0:21:36 > 0:21:40makes them such spectacular and unusually-shaped mountains.
0:21:49 > 0:21:51Now be careful here.
0:21:53 > 0:21:56We are entering in between the boulders.
0:21:56 > 0:21:59- Down there?- Yes.
0:22:01 > 0:22:04You'll be fine if you can hear the river.
0:22:04 > 0:22:06So you can hear the water moving below you?
0:22:06 > 0:22:09Yeah. Yeah, absolutely.
0:22:10 > 0:22:15'No more rain but instead we've got an underground river.
0:22:15 > 0:22:19'Looks like we're going to be staying wet, then.'
0:22:21 > 0:22:23Bye-bye, light.
0:22:30 > 0:22:35'Making our way into the cave over treacherously loose rocks,
0:22:35 > 0:22:38'this isn't a place to lose concentration.
0:22:38 > 0:22:41'as Keith, our cameraman, learns the hard way.'
0:22:44 > 0:22:45Oh, Jesus, KP, are you all right?
0:22:45 > 0:22:47Yeah.
0:22:47 > 0:22:49How are your hands?
0:22:49 > 0:22:50Little minor graze.
0:22:51 > 0:22:55Just trying to protect the camera, that was all. Let's go.
0:22:55 > 0:22:58'If that's the worst the cave can throw at us,
0:22:58 > 0:23:01'we'll be getting off very lightly.'
0:23:10 > 0:23:13'Deeper into the cave, and I'm beginning to appreciate
0:23:13 > 0:23:15'what an astonishing place it is.'
0:23:30 > 0:23:32That's incredibly beautiful.
0:23:32 > 0:23:33Gypsum crystals.
0:23:44 > 0:23:47'This is our new home.
0:23:47 > 0:23:48'We're going to establish a base camp,
0:23:48 > 0:23:52'and spend three full days deep within the Tepui.'
0:23:54 > 0:23:59'Although our main goal is to push into unexplored areas,
0:23:59 > 0:24:01'I also want to search for life.'
0:24:07 > 0:24:09'This cave is millions of years old...
0:24:12 > 0:24:15'..so some of the animals down here have had plenty of time
0:24:15 > 0:24:17'to evolve into new species.'
0:24:25 > 0:24:26'It's just a case of finding them.'
0:24:33 > 0:24:35It's a cricket...
0:24:37 > 0:24:40..that lives in the water and swims.
0:24:40 > 0:24:43And jumps, just like a normal cricket!
0:24:43 > 0:24:47This is one of the top predators inside this cave system.
0:24:47 > 0:24:49They are carnivorous. They feed on other insects,
0:24:49 > 0:24:53tapping around in the dark with those great long antennae,
0:24:53 > 0:24:56searching for food to prey upon.
0:24:56 > 0:24:57This one's a female.
0:24:57 > 0:25:01You can see that scimitar-shaped ovipositor, or egg laying tube,
0:25:01 > 0:25:02at the back of the abdomen there,
0:25:02 > 0:25:05which she uses for laying her eggs.
0:25:05 > 0:25:07But most extraordinary,
0:25:07 > 0:25:11they're most comfortable in and under the water. They're aquatic.
0:25:14 > 0:25:16These are known from several other Tepuis tops,
0:25:16 > 0:25:19but they've probably been separated from each other
0:25:19 > 0:25:21for hundreds of thousands, if not millions of years.
0:25:21 > 0:25:24So it is entirely possible that this one here
0:25:24 > 0:25:27is found only in this cave system.
0:25:27 > 0:25:31that this species could be unique to Auyan Tepui and its caves.
0:25:38 > 0:25:40Knowing my interest in wildlife,
0:25:40 > 0:25:43Francesco has a surprise in store.
0:25:43 > 0:25:46An ancient mystery that he's hoping I can help solve.
0:25:47 > 0:25:49So fragile here.
0:25:51 > 0:25:52Oh, wow.
0:25:55 > 0:25:58Wow, that's incredible.
0:26:03 > 0:26:06This is... This is extraordinary.
0:26:06 > 0:26:09- I don't really know what to say. - What do you think?
0:26:09 > 0:26:12I don't want to jump to any conclusions but,
0:26:12 > 0:26:16it looks like something that absolutely shouldn't be here.
0:26:18 > 0:26:21OK, so... what we've obviously got...
0:26:21 > 0:26:23Let's stick to the obvious first.
0:26:23 > 0:26:26It's a medium-sized mammal,
0:26:26 > 0:26:29almost certainly a carnivore.
0:26:29 > 0:26:32Well, no, certainly a carnivore.
0:26:32 > 0:26:34The way that it's lying here,
0:26:34 > 0:26:37it just looks like it's laid down and died here but,
0:26:37 > 0:26:41- but you can see all, like, tiny like shiny crystals on it.- Yes.
0:26:41 > 0:26:44- So what does that mean? - It's silica crystals.
0:26:44 > 0:26:47- So they formed on the bones? - That's right.
0:26:47 > 0:26:50Can you guess how old this might be?
0:26:50 > 0:26:53In my opinion, to get so much silica on the crystals,
0:26:53 > 0:26:56it has to be some thousands,
0:26:56 > 0:26:58tens of thousands of years.
0:26:58 > 0:27:03OK, well, that's pretty extraordinary!
0:27:03 > 0:27:06One of the best ways of
0:27:06 > 0:27:10finding out things about mammals is their dentition, their teeth.
0:27:10 > 0:27:15And we've got there the remnants of carnassial teeth.
0:27:15 > 0:27:18Those are big cheek teeth that are found here,
0:27:18 > 0:27:21and those are used for slicing up meat.
0:27:21 > 0:27:23This... It's a cat, this is a cat.
0:27:23 > 0:27:28It's much too small for... for puma or jaguar, obviously.
0:27:28 > 0:27:32It's too big for margay or jaguarundi.
0:27:32 > 0:27:34It looks like an ocelot.
0:27:34 > 0:27:35That's incredible!
0:27:37 > 0:27:40This would be the first ever record
0:27:40 > 0:27:46of any kind of wild cat found on the top of a Tepui, ever.
0:27:46 > 0:27:48Which is mind-blowing.
0:27:48 > 0:27:51But it's perhaps even more mind-blowing,
0:27:51 > 0:27:53that this could have been here for thousands of years.
0:27:53 > 0:27:54Almost certainly it has.
0:28:07 > 0:28:10Before we get back to our camp, there's another weird sight.
0:28:12 > 0:28:16In fact, if anything, it's a bit unsettling.
0:28:22 > 0:28:24This is the lake.
0:28:25 > 0:28:28What causes all the colours?
0:28:28 > 0:28:30Bacterial colonies in the water.
0:28:30 > 0:28:34At least 40% of the bacteria living here
0:28:34 > 0:28:37are unknown species for science.
0:28:37 > 0:28:39So what kind of things have you been finding here?
0:28:39 > 0:28:43For example, bacteria which are very close to species like the one
0:28:43 > 0:28:45housing the bubonic plague.
0:28:45 > 0:28:47- The bubonic plague?- Yes.
0:28:47 > 0:28:49You never told me that beforehand!
0:28:49 > 0:28:51Yeah, because probably they are similar
0:28:51 > 0:28:53but they are not aggressive to humans.
0:28:53 > 0:28:54We hope.
0:28:54 > 0:28:55Hopefully.
0:29:02 > 0:29:05Settling down for our first night underground,
0:29:05 > 0:29:08it's the plague that's on everyone's mind.
0:29:08 > 0:29:10Who's pinched my cup?
0:29:10 > 0:29:12See, nothing's safe around here, is it?
0:29:12 > 0:29:15- Well, we've all got the plague, so it doesn't matter.- Exactly.
0:29:15 > 0:29:16THEY LAUGH
0:29:19 > 0:29:22'I'm more worried by something a bit more tangible.'
0:29:22 > 0:29:25Last thing you want sand in your sleeping bag.
0:29:28 > 0:29:31'But it isn't dry sand or the plague that's the problem.'
0:29:37 > 0:29:41'Aldo's the first to realise something's wrong.
0:29:41 > 0:29:42'He's woken by the sound of rushing water.'
0:29:48 > 0:29:53Well, basically, where we are sleeping, it's running fast.
0:29:54 > 0:29:57Pretty scary, that noise.
0:29:57 > 0:29:59It's obviously been hammering it down.
0:30:03 > 0:30:06It just goes to show how quickly this environment can go from
0:30:06 > 0:30:09almost benign to, to deadly, really.
0:30:16 > 0:30:17If it does get any worse,
0:30:17 > 0:30:20we need to make our way up on to this high ground.
0:30:25 > 0:30:26It turns out we're in luck.
0:30:26 > 0:30:30The water level peaks soon after.
0:30:30 > 0:30:32We'll just have to take turns through the night,
0:30:32 > 0:30:35keep an eye on it, listen out for the noise.
0:30:37 > 0:30:41'Dropping off, I expect to be woken by water lapping round my ears.'
0:30:47 > 0:30:50'When I wake, I'm still knackered.'
0:30:50 > 0:30:51Just ten more minutes.
0:30:53 > 0:30:54'Who says it's morning anyway?
0:30:54 > 0:30:57'Hard to tell when you're in perpetual darkness.'
0:31:01 > 0:31:05Oh, I just love putting the cold, wet cave suit back on again.
0:31:05 > 0:31:10Urgh, soggy for the rest of the day. Hooray.
0:31:18 > 0:31:21'Day two, and there's one question that needs sorting out.
0:31:21 > 0:31:23'How were these caves formed?'
0:31:28 > 0:31:30'Tepuis are made from quartzite sandstone,
0:31:30 > 0:31:33'and that's one of the hardest rocks on earth.
0:31:33 > 0:31:35'Caves just don't belong here.'
0:31:38 > 0:31:40'But Francesco is a geologist,
0:31:40 > 0:31:42'and he's been working on an answer to the mystery.'
0:31:46 > 0:31:49'It begins with the strange pillars that line these galleries.'
0:32:12 > 0:32:14'You'd think the water did its work of erosion
0:32:14 > 0:32:17'by just wearing down the rock.
0:32:17 > 0:32:19'But Francesco thinks not.'
0:32:21 > 0:32:23Yeah.
0:32:32 > 0:32:34Wow.
0:32:39 > 0:32:41'The water isn't wearing the rock away,
0:32:41 > 0:32:45'it's dissolving the bonds that give the rock its strength.
0:32:45 > 0:32:49'It's a chemical process that gradually turns hard sandstone
0:32:49 > 0:32:52'back into sand.
0:32:52 > 0:32:55'Effectively, the Tepui is rotting from within.'
0:33:00 > 0:33:02'Over millions of years,
0:33:02 > 0:33:04'this hollows out vast galleries,
0:33:04 > 0:33:07'and leaves behind these ever-dwindling columns.'
0:33:12 > 0:33:15What happens when that finally goes?
0:33:16 > 0:33:19- So you just get a huge, huge fall? - Yeah.
0:33:19 > 0:33:22And is that an important process for the Tepuis?
0:33:32 > 0:33:35- Oh, OK, so it's not just forming inside the caves.- No.
0:33:35 > 0:33:37But the whole Tepui.
0:33:45 > 0:33:50The distinctive summits of the Tepuis are cut with deep gorges,
0:33:50 > 0:33:54that have been shaped by the collapse of these underground caves.
0:33:55 > 0:33:58There are even places where you can see the remains of cave systems,
0:33:58 > 0:34:00exposed on the surface.
0:34:02 > 0:34:05But the influence of water rotting the rock
0:34:05 > 0:34:08also shapes the Tepuis in another way.
0:34:11 > 0:34:13The big vertical rock walls that you get on Tepuis,
0:34:13 > 0:34:15are they related to this?
0:34:29 > 0:34:34The tops of the Tepuis are littered with deep vertical fractures.
0:34:36 > 0:34:39As water percolates into these cracks,
0:34:39 > 0:34:40it rots the sandstone,
0:34:40 > 0:34:42just as it does in the cave.
0:34:42 > 0:34:44Over time the cracks get bigger,
0:34:44 > 0:34:47until the rock falls away.
0:34:47 > 0:34:49Leaving behind huge cliffs.
0:34:54 > 0:34:58After the repeated soaking we've had throughout the trip,
0:34:58 > 0:35:01perhaps it shouldn't be a surprise that water is responsible
0:35:01 > 0:35:04for creating these huge isolated peaks.
0:35:11 > 0:35:15'But it is surprising that only underground
0:35:15 > 0:35:17'do you get to see how the process works.'
0:35:22 > 0:35:25'Our final night in the cave.
0:35:25 > 0:35:28'Tomorrow will be a step into the unknown.'
0:35:29 > 0:35:31'We're going to try and break through
0:35:31 > 0:35:34'into a previously unexplored area of the cave.'
0:35:36 > 0:35:38You can feel there's a whole different attitude
0:35:38 > 0:35:40around the camp this evening.
0:35:40 > 0:35:43A kind of sense of anticipation and excitement,
0:35:43 > 0:35:46and it's that not knowing what's ahead.
0:35:46 > 0:35:50The idea of going somewhere that no-one's ever been before
0:35:50 > 0:35:51is a very powerful one.
0:35:51 > 0:35:54Very, very exciting.
0:35:55 > 0:35:57But also daunting.
0:35:57 > 0:35:59Who knows what we'll find?
0:36:08 > 0:36:09'Our final day,
0:36:09 > 0:36:13'and we tramp down familiar passages following one particular lead.'
0:36:15 > 0:36:17'The cavers had previously encountered a collapse
0:36:17 > 0:36:19'at the far reaches of the system,
0:36:19 > 0:36:21'and believe that there might be
0:36:21 > 0:36:25'a whole new section of unexplored cave on the other side of it.'
0:36:27 > 0:36:29'Leaving the rest of the team behind,
0:36:29 > 0:36:32'Aldo, Keith and I join Francesco to investigate.'
0:36:36 > 0:36:40You see the gallery here on this collapse.
0:36:40 > 0:36:44But I think that behind the collapse the galleries continue.
0:36:45 > 0:36:47'This is it.
0:36:47 > 0:36:50'If we can get beyond that shattered rock,
0:36:50 > 0:36:53'we'll be treading where no human has ever been before.'
0:36:57 > 0:36:59'But we're heading into trouble.'
0:37:07 > 0:37:09This rock shows how careful you have to be
0:37:09 > 0:37:11as you're moving through these passages.
0:37:11 > 0:37:15It's pretty big, probably weighs about half a ton,
0:37:15 > 0:37:19and it's held in place by a couple of fixtures of sand.
0:37:19 > 0:37:22If you put your hand on that the whole thing would come down.
0:37:24 > 0:37:26Go careful there, careful.
0:37:31 > 0:37:34How does it look down there?
0:37:34 > 0:37:36There is a passage but a narrow one.
0:38:02 > 0:38:04Just don't touch any of that stuff to your left-hand side.
0:38:04 > 0:38:05Don't touch any of it.
0:38:08 > 0:38:11This is the... the floor of the cave,
0:38:11 > 0:38:14- of the gallery... of the gallery. - Yeah.
0:38:14 > 0:38:17This is a good way, but we have to see if it's open.
0:38:17 > 0:38:19What do you think?
0:38:19 > 0:38:22We could try to go here.
0:38:22 > 0:38:23It's a squeeze.
0:38:23 > 0:38:28It's a squeeze but it's worth to try because I can feel some air coming.
0:38:34 > 0:38:37'The air coming out of the passage must be coming from somewhere.
0:38:37 > 0:38:39'That's the theory anyway.'
0:38:45 > 0:38:48This is the bit of caving I don't like.
0:38:48 > 0:38:49Squeezes.
0:38:54 > 0:38:55I'm not built for this.
0:39:03 > 0:39:05I just hope if this doesn't lead anywhere,
0:39:05 > 0:39:07I've got enough room to turn around.
0:39:27 > 0:39:30I've got it, I think. Yeah, I've got it.
0:39:43 > 0:39:45'Mercifully, the passage widens.'
0:39:53 > 0:39:56On the other side is a new section of the cave,
0:39:56 > 0:39:58that no human has ever set eyes on.
0:40:00 > 0:40:05This place has never seen light in 40 or 50 million years
0:40:05 > 0:40:06until now.
0:40:11 > 0:40:15The whole ceiling's collapsed. We've got our first open amphitheatre.
0:40:15 > 0:40:17Absolutely beautiful.
0:40:20 > 0:40:25- Here the cave is becoming bigger, so it's worth to make a map.- OK.
0:40:28 > 0:40:29- OK, Steve?- Yeah.
0:40:29 > 0:40:34Can you find a spot there where I can see you?
0:40:34 > 0:40:36Maybe there?
0:40:36 > 0:40:37OK, here?
0:40:45 > 0:40:48'Discovering new areas of the cave isn't just for kicks.'
0:40:50 > 0:40:54'Francesco's maps are changing the way we think about the Tepuis.'
0:40:56 > 0:40:58'Although they're made from hard rock,
0:40:58 > 0:41:01'it's becoming clear they're like a Swiss cheese,
0:41:01 > 0:41:04'riddled with passages and caverns.'
0:41:11 > 0:41:13'So far, so good.'
0:41:16 > 0:41:20'But there's one more unexplored collapse that Francesco thinks
0:41:20 > 0:41:22'might link back to the known cave system.'
0:41:25 > 0:41:28So now we can have a look down.
0:41:28 > 0:41:30Yeah.
0:41:30 > 0:41:32This way, because I think that we would
0:41:32 > 0:41:36have to arrive to the deepest section of the river.
0:41:36 > 0:41:39- OK.- So this way.
0:41:40 > 0:41:43'That matter of fact tone doesn't fool me.'
0:41:43 > 0:41:46It's like walking on razor blades!
0:41:49 > 0:41:50Yeah, that's peeling off.
0:41:50 > 0:41:53You can see the facture line right down here.
0:41:56 > 0:42:00- Welcome to the narrow caves.- Yeah!
0:42:01 > 0:42:03How's it looking, Francesco?
0:42:03 > 0:42:05Continuing very flat.
0:42:05 > 0:42:06Yeah.
0:42:06 > 0:42:08Shall we come?
0:42:08 > 0:42:11You can, but be careful with the roof!
0:42:12 > 0:42:14Don't touch the roof!
0:42:14 > 0:42:15OK.
0:42:19 > 0:42:21'It's another squeeze,
0:42:21 > 0:42:24'but this time littered with scalpel-sharp rocks,
0:42:24 > 0:42:26'and a dangerously loose ceiling.'
0:42:27 > 0:42:31'Basically all of my worst caving nightmares rolled into one.'
0:42:31 > 0:42:37This place has been undisturbed for tens of millions of years.
0:42:37 > 0:42:41It seems incredible that just a single nudge could bring down
0:42:41 > 0:42:45something big, but it could, so we have to proceed with real caution.
0:42:45 > 0:42:48Someone getting trapped underneath one of these big rocks or
0:42:48 > 0:42:51a broken arm, or broken leg down here would just be unthinkable.
0:42:51 > 0:42:54OK, so everyone, proceed with caution.
0:43:25 > 0:43:28Oh, that slab above me looks horrible.
0:43:28 > 0:43:30That's really, really loose.
0:43:40 > 0:43:43Oh, I don't like this at all.
0:43:47 > 0:43:51There's about one foot between the ceiling and the deck,
0:43:51 > 0:43:52and it's so loose.
0:43:54 > 0:43:56Just slowly, slowly does it.
0:44:05 > 0:44:07It's not a very safe place.
0:44:07 > 0:44:09You're in a safe place?
0:44:09 > 0:44:12- It's not safe. - It's not safe?
0:44:12 > 0:44:13No.
0:44:14 > 0:44:16'Well, I'm glad we got THAT clear.'
0:44:22 > 0:44:25This is, if I'm honest, pretty desperate.
0:44:25 > 0:44:29It's like sliding around on a bed of knives,
0:44:29 > 0:44:32hoping the sky doesn't fall in.
0:44:32 > 0:44:34All I hope is that we don't hit a dead end,
0:44:34 > 0:44:37cos I don't want to come back through this, ever again.
0:44:41 > 0:44:44It's all down to Francesco.
0:44:44 > 0:44:45Can he find a way through?
0:45:06 > 0:45:10OK, it's getting bigger!
0:45:10 > 0:45:11Great!
0:45:15 > 0:45:19'After several hours of nerve-shredding tension,
0:45:19 > 0:45:22'finally we can stand up.'
0:45:29 > 0:45:32Don't worry about the rucksack, Aldo, it's a bit of kit.
0:45:32 > 0:45:34- Are you all right, buddy?- Yeah.
0:45:34 > 0:45:36That was pretty sketchy, wasn't it?
0:45:36 > 0:45:40Did you see the huge chunks that were fresh on top without the dust?
0:45:40 > 0:45:43Which means, you know, some of it is probably thousands of years old,
0:45:43 > 0:45:47- some of it is probably a few weeks old.- Yeah, yep.
0:45:47 > 0:45:50This is not a nice place to hang about, is it?
0:45:50 > 0:45:52- No, let's get out, then. - Let's get moving.
0:45:59 > 0:46:01OK.
0:46:06 > 0:46:09'Francesco's instincts haven't let him down.
0:46:09 > 0:46:11'We've been spat out into the deepest point
0:46:11 > 0:46:13'of the known cave system.'
0:46:17 > 0:46:20So we're back at the main river. We've completed a loop.
0:46:20 > 0:46:24'Mission accomplished, it's time to follow the river
0:46:24 > 0:46:26'and return to the surface.'
0:46:29 > 0:46:33'But Francesco keeps hinting there's one last surprise.'
0:46:45 > 0:46:46Whoa.
0:46:48 > 0:46:50This is beautiful.
0:47:05 > 0:47:08My dream is to explore, to go places no-one's been before.
0:47:08 > 0:47:10Places like this.
0:47:13 > 0:47:18A waterfall tumbling into a cave on the top of a 2,000-metre mountain.
0:47:18 > 0:47:20There's not many places on the planet you can see that.
0:47:24 > 0:47:26And blue, blue sky above.
0:47:29 > 0:47:32We've spent most of the day scrambling around in a passageway
0:47:32 > 0:47:35that has never seen light.
0:47:37 > 0:47:39Now I guess we have to head back,
0:47:39 > 0:47:43but I just want to spend a few more minutes here, enjoying this place.
0:47:49 > 0:47:51Amazing.
0:47:51 > 0:47:54'What a place to end our cave adventure.'
0:48:04 > 0:48:07'It's time to move on to the final stage of our expedition.'
0:48:12 > 0:48:15We are leaving the dark world of the caves behind,
0:48:15 > 0:48:18and heading to the next spectacular phase of our expedition.
0:48:18 > 0:48:22One of the most iconic natural wonders on the planet.
0:48:33 > 0:48:36'And I'm looking forward to meeting up with the climbing team again.
0:48:36 > 0:48:39'They've been busy preparing a truly spectacular end
0:48:39 > 0:48:41'to our Venezuelan adventure.'
0:48:46 > 0:48:52- John, how you doing?- Great, great. - Good to see you. Hola, hola.
0:48:52 > 0:48:55- How was it?- Yeah, really good, really good.
0:48:55 > 0:48:58- So you have something special planned for us?- Yeah.
0:48:58 > 0:49:01We have a great plan. More than grand. It's fantastic.
0:49:01 > 0:49:03That's what we like to hear.
0:49:04 > 0:49:09'Our final challenge is to get down from the summit of Auyan Tepui.'
0:49:10 > 0:49:13'Obviously we could take the chopper,
0:49:13 > 0:49:15'but there's a more exciting way.'
0:49:17 > 0:49:19'Not only is it going to be breathtaking,
0:49:19 > 0:49:22'but it will allow us to see these mountains,
0:49:22 > 0:49:26'and their sheer-sided cliffs up close one last time.'
0:49:29 > 0:49:32Just making our way towards the edge now.
0:49:32 > 0:49:34At the moment it's shrouded in cloud,
0:49:34 > 0:49:38but it's a billowing, moving cloud and could clear at any second.
0:49:38 > 0:49:42And when it does, I think it's going to be pretty spectacular.
0:49:45 > 0:49:49Listen to that noise. It's like a thundering roar.
0:49:49 > 0:49:53And I can just see down below, there's a thousand metres,
0:49:53 > 0:49:55nearly 3,000 feet below,
0:49:55 > 0:49:58a huge carpet of rainforest.
0:49:59 > 0:50:01It's clearing, it's clearing!
0:50:10 > 0:50:13That is one of the most beautiful things I've ever seen.
0:50:18 > 0:50:20This is the Angel Falls.
0:50:20 > 0:50:24979 metres - that's nearly a kilometre of cascading water,
0:50:24 > 0:50:26tumbling down to the forest beneath.
0:50:29 > 0:50:32I don't get any sense of fear over heights normally.
0:50:32 > 0:50:35I mean, you couldn't be a mountaineer and get vertigo,
0:50:35 > 0:50:39but seriously, looking over that edge is just gut-wrenching.
0:50:39 > 0:50:42Puts your stomach in the back of your mouth.
0:50:45 > 0:50:48This expedition has been dominated by water.
0:50:48 > 0:50:50The clouds circling around our ears,
0:50:50 > 0:50:53the constant battering of rain, following the river right
0:50:53 > 0:50:57through the inside of the Tepui and now finally, we're going to
0:50:57 > 0:51:00follow that water as it cascades over the edge of the mountain.
0:51:00 > 0:51:04Tomorrow morning, we're getting on a pair of tiny ropes,
0:51:04 > 0:51:06no bigger than my little finger, and we're going to
0:51:06 > 0:51:11drop off into the abyss, alongside the highest waterfall on earth.
0:51:11 > 0:51:14I can't think of a more fitting finale
0:51:14 > 0:51:17to what has been an extraordinary adventure.
0:51:34 > 0:51:38'The next morning, final preparations for our descent
0:51:38 > 0:51:39'are well under way.'
0:51:41 > 0:51:46We're about to start abseiling down it and my initial thoughts are,
0:51:46 > 0:51:48"It's absolutely spectacular."
0:51:52 > 0:51:53'The view is impressive.'
0:51:56 > 0:51:59'But it's nothing compared to what we're about to experience.'
0:52:00 > 0:52:03'It's time to launch myself down the cliff.'
0:52:03 > 0:52:06OK, last few checks.
0:52:08 > 0:52:09Everything good to go.
0:52:20 > 0:52:21Pretty dizzying.
0:52:25 > 0:52:26Whoa.
0:52:27 > 0:52:29It's a very, very long way up.
0:52:37 > 0:52:40OK, this is always the nervy bit...
0:52:43 > 0:52:47..going from good solid rock into open air.
0:52:49 > 0:52:51Whoa!
0:52:53 > 0:52:55That is out of this world!
0:53:04 > 0:53:08I feel like a very tiny spider on one single thin line of silk.
0:53:12 > 0:53:16Honestly, it's one of the most extraordinary views I've ever seen.
0:53:23 > 0:53:28I have the huge forest valley below me,
0:53:28 > 0:53:31and the world's biggest waterfall off to the side of me.
0:53:31 > 0:53:33This is awesome.
0:53:37 > 0:53:41'I'm no stranger to grand views from a great height,
0:53:41 > 0:53:43'but this is something truly special.'
0:53:46 > 0:53:50Whoa!
0:53:52 > 0:53:56- Nice.- That is... "Nice"?!
0:53:56 > 0:53:58That's the understatement of the millennium.
0:54:02 > 0:54:06'And the rest of the team clearly feel the same way.'
0:54:06 > 0:54:07Wow.
0:54:07 > 0:54:11It's... I'm speechless!
0:54:14 > 0:54:18'But this is only the beginning.
0:54:18 > 0:54:19'There are over 30 more abseils
0:54:19 > 0:54:22'between this ledge and the jungle below.'
0:54:24 > 0:54:26That's it. The only way is down.
0:54:28 > 0:54:31'It's obviously going to be punishing work
0:54:31 > 0:54:32'getting off this Tepui.'
0:54:41 > 0:54:42Give it a pull.
0:54:44 > 0:54:45Thank you.
0:54:50 > 0:54:51Three, two, one.
0:54:55 > 0:54:57Keep low!
0:55:02 > 0:55:05'Eventually we arrive at the base of the cliffs,
0:55:05 > 0:55:08'and onto an outcrop with a magnificent view of Angel Falls.'
0:55:09 > 0:55:12This is our last view point of the falls.
0:55:12 > 0:55:15It's pretty special isn't it? It's mesmerising, it's hypnotic.
0:55:15 > 0:55:18Yeah, it is. It would be like jungle abseiling
0:55:18 > 0:55:20from here to the bottom.
0:55:20 > 0:55:22'Although we still have several hours of descending
0:55:22 > 0:55:25'through dense rainforest to go,
0:55:25 > 0:55:28'this view of Angel Falls, from the rocky outcrop,
0:55:28 > 0:55:30'feels to me like the moment that we leave
0:55:30 > 0:55:33'the world of the Tepuis behind.'
0:55:33 > 0:55:37This has been a really remarkable expedition.
0:55:37 > 0:55:41Places like the Angel Falls makes you feel like an explorer.
0:55:41 > 0:55:42It makes you feel that
0:55:42 > 0:55:46there are still incredible things to be discovered.
0:55:46 > 0:55:50There is a real purpose to exploration, especially now
0:55:50 > 0:55:53because so much of our planet is being lost,
0:55:53 > 0:55:56is being destroyed by us as human beings.
0:55:56 > 0:55:59The parts that we can discover afresh with new eyes
0:55:59 > 0:56:02and learn to treasure, you know, we're going to want to try
0:56:02 > 0:56:05and preserve them, and that's incredibly important.
0:56:05 > 0:56:08Otherwise, sights like this are going to be lost,
0:56:08 > 0:56:10and my children will never get a chance to see them.
0:56:14 > 0:56:18'This expedition to shed new light on the Tepuis of Venezuela,
0:56:18 > 0:56:20'will hold so many memories for me.
0:56:20 > 0:56:23'I travelled by land...
0:56:23 > 0:56:26'water...
0:56:26 > 0:56:27'and air.'
0:56:27 > 0:56:29No way!
0:56:29 > 0:56:31'And was almost killed by a plane.'
0:56:34 > 0:56:38'I tried to conquer cliffs that had never been climbed.
0:56:38 > 0:56:41'But was forced to retreat when pushed beyond my limits.'
0:56:41 > 0:56:43No, no, no, no!
0:56:45 > 0:56:47'I experienced the otherworldly beauty
0:56:47 > 0:56:49'and intense claustrophobia,
0:56:49 > 0:56:51'hidden deep within the mountain.'
0:56:51 > 0:56:54I don't like this at all.
0:56:54 > 0:56:57'And ventured where no-one had been before.'
0:56:58 > 0:56:59'I encountered exotic...'
0:56:59 > 0:57:02Oh, it hurts so much!
0:57:02 > 0:57:06'..strange, and dangerous creatures.'
0:57:08 > 0:57:10Whoa!
0:57:10 > 0:57:13'Finally I abseiled alongside the world's highest waterfall.'
0:57:16 > 0:57:18'And I will never forget the camaraderie of the people
0:57:18 > 0:57:20'I shared this adventure with.
0:57:20 > 0:57:23'So I'm leaving this fabulous land,
0:57:23 > 0:57:25'not only with a sense of immense achievement,
0:57:25 > 0:57:28'but also knowing that there is still
0:57:28 > 0:57:31'an untold amount yet to discover.'
0:57:31 > 0:57:35We may not have achieved everything that we set out to do here,
0:57:35 > 0:57:38but I don't think that's a failure, far from it.
0:57:38 > 0:57:41In fact, I think it's a really powerful idea
0:57:41 > 0:57:44that there are still landscapes that are stronger than us,
0:57:44 > 0:57:47places that we can't tame.
0:57:47 > 0:57:49And I, for one, am definitely going to be back.