The Ancient Highway

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0:00:02 > 0:00:04BBC Four Collections -

0:00:04 > 0:00:07specially chosen programmes from the BBC archive.

0:00:07 > 0:00:09For this collection, Sir David Attenborough

0:00:09 > 0:00:13has chosen documentaries from the start of his career.

0:00:13 > 0:00:16More programmes on this theme, and other BBC Four Collections,

0:00:16 > 0:00:18are available on BBC iPlayer.

0:00:22 > 0:00:25DRUMS BEAT

0:00:25 > 0:00:28PEOPLE CHANTING

0:01:09 > 0:01:12DAVID ATTENBOROUGH: The largest single sheet of falling water

0:01:12 > 0:01:15in the world. A mile and a quarter long.

0:01:15 > 0:01:17The Victoria Falls.

0:01:21 > 0:01:24Here the Zambezi plunges over a cliff

0:01:24 > 0:01:28and thunders into a chasm 350 feet deep.

0:01:31 > 0:01:34The cliff into which the entire river pours

0:01:34 > 0:01:37runs parallel to the line of the falls

0:01:37 > 0:01:40and is only a mere 100 yards across.

0:01:42 > 0:01:46Clouds of spray swirl up in such volume

0:01:46 > 0:01:49that they condense on the opposite side of the chasm

0:01:49 > 0:01:51to form new cascades.

0:01:51 > 0:01:53But these never reach the bottom again,

0:01:53 > 0:01:57for the enormous volume of water crashing into the gorge

0:01:57 > 0:01:59causes such a tremendous updraught of air

0:01:59 > 0:02:01that it catches these streams

0:02:01 > 0:02:03and once more blows them into the sky.

0:02:09 > 0:02:13At a few places, you can scramble down into the gorge itself.

0:02:15 > 0:02:18Down here, at the foot of the falls,

0:02:18 > 0:02:20the spray from the tumbling water

0:02:20 > 0:02:24keeps these gorges saturated in moisture.

0:02:24 > 0:02:26And, as a result, all sorts of plants grow here

0:02:26 > 0:02:29that are not found at the top of the falls.

0:02:29 > 0:02:32These palms, for example, wouldn't grow

0:02:32 > 0:02:35on the sun-baked, parched land 300 feet above.

0:02:35 > 0:02:36And as a result of that,

0:02:36 > 0:02:40there are all sorts of birds and animals that live here

0:02:40 > 0:02:43that are not found up above.

0:02:43 > 0:02:47Among them are the little hyraxes.

0:02:47 > 0:02:49A hyrax looks a bit like a rabbit,

0:02:49 > 0:02:52but, in fact, it's quite unrelated.

0:02:52 > 0:02:54Indeed, its exact relations are something of a mystery.

0:02:54 > 0:02:57But from the nature of its teeth and its feet,

0:02:57 > 0:02:59people think that it's related, perhaps,

0:02:59 > 0:03:02to the elephant, surprisingly enough.

0:03:02 > 0:03:05Anyway, they live among those boulders over there.

0:03:05 > 0:03:08At the moment, I can't see any at all.

0:03:08 > 0:03:11But the hyrax has a very high-pitched whistle,

0:03:11 > 0:03:14and I'm going to see if I can't persuade some of them to come out

0:03:14 > 0:03:17by blowing on this very high-pitched dog whistle.

0:03:19 > 0:03:24HE BLOWS WHISTLE

0:03:30 > 0:03:33HE BLOWS WHISTLE

0:03:33 > 0:03:37WHISTLING CONTINUES

0:03:42 > 0:03:45Hyrax, or dassies - as they're called in these parts -

0:03:45 > 0:03:48live in small, family colonies.

0:03:48 > 0:03:51They're about a foot long and vegetarians.

0:03:51 > 0:03:54But only during the night and at dusk and dawn

0:03:54 > 0:03:56do they venture away

0:03:56 > 0:04:00from the security of their rocky labyrinths in order to graze.

0:04:00 > 0:04:02During the daylight hours,

0:04:02 > 0:04:04they spend most of their time

0:04:04 > 0:04:07basking in the sun on the hot boulders.

0:04:08 > 0:04:10They have few enemies.

0:04:10 > 0:04:12A leopard, maybe.

0:04:12 > 0:04:13Man, of course.

0:04:13 > 0:04:16And hawks.

0:04:16 > 0:04:19But when the shadow of a hovering, hunting hawk

0:04:19 > 0:04:20drifts over the boulders,

0:04:20 > 0:04:23then the hyrax quickly scamper to safety.

0:04:27 > 0:04:32On the river above the falls, there is an abundance of animal life

0:04:32 > 0:04:34and of the most spectacular kind.

0:04:38 > 0:04:43THROATY RUMBLING

0:04:43 > 0:04:45ELEPHANT ROARS

0:04:49 > 0:04:53Elephants don't like you to approach too closely.

0:04:53 > 0:04:56And once they've caught your scent through their uplifted trunks,

0:04:56 > 0:05:00they can behave in a somewhat alarming way.

0:05:00 > 0:05:02But however threatening they may seem,

0:05:02 > 0:05:05you're usually pretty safe in a boat on the river

0:05:05 > 0:05:07for they seldom charge into the water.

0:05:09 > 0:05:12They are immensely destructive creatures,

0:05:12 > 0:05:16and they have to be, in order to satisfy their vast appetites.

0:05:16 > 0:05:19An adult elephant munches about

0:05:19 > 0:05:21five hundredweight of vegetation a day.

0:05:21 > 0:05:25There are still large numbers of them on this part of the Zambezi.

0:05:25 > 0:05:29So many, in fact, that in parts they've devastated the bush.

0:05:29 > 0:05:33Herds roam close to the outskirts of the town of Livingstone,

0:05:33 > 0:05:34beside the Victoria Falls,

0:05:34 > 0:05:37and every evening plod across the main road

0:05:37 > 0:05:39on their way down to the river to drink,

0:05:39 > 0:05:42so that a motorist coming fast round a corner at night

0:05:42 > 0:05:45has to be ready to jam on his brakes in a hurry.

0:06:10 > 0:06:14Like all game, elephants are dependent on water.

0:06:14 > 0:06:19Every day they drink between 30 to 50 gallons, if they can get it,

0:06:19 > 0:06:21so that in times of drought

0:06:21 > 0:06:23a herd can quickly suck a waterhole dry.

0:06:25 > 0:06:29The technique of drinking by putting your nose in the water,

0:06:29 > 0:06:32sniffing up a trunk full, and then blowing it back into your mouth,

0:06:32 > 0:06:37is not one which, apparently, comes naturally even to elephants.

0:06:37 > 0:06:40The little babies, when they first come down,

0:06:40 > 0:06:43take some time to learn the trick.

0:06:43 > 0:06:47Occasionally, you can see a really young one imitate its elders

0:06:47 > 0:06:50by dipping its tiny, stubby trunk into the water,

0:06:50 > 0:06:52and then putting it straight into its mouth,

0:06:52 > 0:06:55without realising that if you want to drink like that

0:06:55 > 0:06:59you must take a sniff in between the two actions.

0:06:59 > 0:07:02Finally, it has to give up and go down on its knees

0:07:02 > 0:07:04and drink directly with its mouth.

0:07:14 > 0:07:16ELEPHANT RUMBLES

0:07:18 > 0:07:21ELEPHANT RUMBLES

0:07:22 > 0:07:26After drinking, the elephants attend to their toilet.

0:07:26 > 0:07:30And there's nothing they enjoy more than a good mud bath,

0:07:30 > 0:07:34splashing one another by swinging their feet in the black mud.

0:07:34 > 0:07:38The little babies almost recklessly frolic in the wallows

0:07:38 > 0:07:41between the legs of their six-tonne mothers.

0:07:41 > 0:07:44It seems a miracle that none ever gets sat on.

0:07:44 > 0:07:47Sometimes the adults themselves abandon their dignity

0:07:47 > 0:07:50and lie down and wallow with the babies.

0:07:50 > 0:07:52But usually they cover themselves with mud

0:07:52 > 0:07:54simply by squirting it

0:07:54 > 0:07:57with astonishing accuracy over their backs.

0:08:05 > 0:08:09ELEPHANTS ROAR AND TRUMPET

0:08:29 > 0:08:34When everyone is nicely covered in glistening, black mud,

0:08:34 > 0:08:37then they powder themselves off with a dust bath.

0:08:58 > 0:09:01This bull, with his trunk resting on his tusk

0:09:01 > 0:09:02and his forelegs crossed,

0:09:02 > 0:09:06is patiently waiting for the ladies to finish their toilet.

0:09:09 > 0:09:11The lives of a whole host of creatures

0:09:11 > 0:09:14revolve around elephants and their activities.

0:09:14 > 0:09:17When the herd has left the waterhole,

0:09:17 > 0:09:19the ground is littered with their droppings.

0:09:19 > 0:09:23And then, down come the hornbills.

0:09:23 > 0:09:27For elephant dung is often full of camel thorn seeds.

0:09:27 > 0:09:30The hornbills can't get these directly from the tree,

0:09:30 > 0:09:33because there the seeds are enclosed in a hard pod,

0:09:33 > 0:09:36which the birds can't crack.

0:09:36 > 0:09:37So, if it wasn't for the elephants,

0:09:37 > 0:09:40the hornbills couldn't enjoy this particular food.

0:09:47 > 0:09:52Oddly enough, the camel thorn tree also is dependent on the elephant.

0:09:52 > 0:09:57Its seeds not only have a hard pod, but an extremely tough rind.

0:09:57 > 0:09:59If they drop from the tree directly onto the ground,

0:09:59 > 0:10:01few of them will germinate.

0:10:01 > 0:10:04Only when they've been chewed by the elephant

0:10:04 > 0:10:08and have been softened by its digestive juices will they sprout.

0:10:13 > 0:10:17Elephant dung is much relished by termites.

0:10:18 > 0:10:20And in search of the termites

0:10:20 > 0:10:23come troops of banded mongeese.

0:10:28 > 0:10:31MONGEESE SQUEAK

0:10:31 > 0:10:34Insatiably curious, they examine everything,

0:10:34 > 0:10:37squeaking with excitement, turning over the dung

0:10:37 > 0:10:39and eating not only the termites

0:10:39 > 0:10:42but beetles and any other little creatures that they can find there.

0:10:48 > 0:10:52MONGEESE SQUEAK

0:10:58 > 0:11:02In fact, animals of all sorts swarm around the Zambezi

0:11:02 > 0:11:05both above and below the falls.

0:11:08 > 0:11:12Even the falls themselves provide a home for special birds.

0:11:12 > 0:11:14A colony of swifts, which every day

0:11:14 > 0:11:17swoop across the curtain of falling water

0:11:17 > 0:11:18in search of insects.

0:11:22 > 0:11:25This huge fissure in the surface of the Earth

0:11:25 > 0:11:28is the creation of the river itself,

0:11:28 > 0:11:31for here it flows over a sheet of basalt rock,

0:11:31 > 0:11:35which is crossed by a series of parallel faults.

0:11:35 > 0:11:38And by pounding relentlessly along one of these

0:11:38 > 0:11:41the river has gouged out this gigantic trench.

0:11:48 > 0:11:51Waterfalls, from our point of view,

0:11:51 > 0:11:53seem to be very permanent features of the landscape.

0:11:53 > 0:11:57This one has hardly changed at all since Livingstone discovered it,

0:11:57 > 0:12:00over a century ago, in 1855.

0:12:00 > 0:12:03This picture, which was painted by Thomas Baines

0:12:03 > 0:12:06only seven years after Livingstone was here,

0:12:06 > 0:12:09matches almost exactly the scene as it is today.

0:12:13 > 0:12:16But in terms of the geological history of the world

0:12:16 > 0:12:19they're very, very temporary affairs.

0:12:19 > 0:12:23The waters of the Zambezi, that have already eroded this chasm

0:12:23 > 0:12:25along a line of weakness through the basalt,

0:12:25 > 0:12:28have now discovered another line of weakness

0:12:28 > 0:12:31which stretches from here at the western end

0:12:31 > 0:12:33diagonally in that direction.

0:12:33 > 0:12:38Slowly and inexorably, the waters are working their way along there.

0:12:38 > 0:12:40Already, the Devil's Cataract here

0:12:40 > 0:12:43is considerably lower than the main line of the falls.

0:12:43 > 0:12:47It may take many thousands of years, but eventually

0:12:47 > 0:12:49the Victoria Falls will migrate

0:12:49 > 0:12:52and move into a new channel over there.

0:12:52 > 0:12:54And when that happens, the present chasm

0:12:54 > 0:12:57will be yet another in the line of gorges

0:12:57 > 0:13:00which follow it downstream.

0:13:10 > 0:13:13Below the falls, the Zambezi,

0:13:13 > 0:13:16which so recently was a mile and a quarter wide,

0:13:16 > 0:13:21is now compressed into a channel no more than 50 yards across.

0:13:21 > 0:13:23Each of these zigzag lines

0:13:23 > 0:13:27of the deep, desolate gorges through which the river boils

0:13:27 > 0:13:30has been excavated by the river itself.

0:13:30 > 0:13:34And each marks the site of the falls in bygone centuries.

0:13:47 > 0:13:5030 or 40 thousand years ago, the waters of the Zambezi

0:13:50 > 0:13:54were thundering over this line of cliffs behind me.

0:13:54 > 0:13:56It's taken them all that time

0:13:56 > 0:13:58to work their way up the seven miles of gorges

0:13:58 > 0:14:01from here to the present line of the falls.

0:14:01 > 0:14:04People haven't always thought that the falls were necessarily beautiful.

0:14:04 > 0:14:07The Portuguese who came here in the 1870s described them

0:14:07 > 0:14:09as being "sublimely horrible".

0:14:09 > 0:14:11And a Frenchman who came along in the '90s

0:14:11 > 0:14:13called them "a veritable hell".

0:14:13 > 0:14:17But no-one can remain indifferent to this tremendous sight.

0:14:17 > 0:14:20The Africans of Livingstone's time regarded the place as sacred

0:14:20 > 0:14:23and buried their dead on the islands above the lip of the falls.

0:14:23 > 0:14:27And there are even indications that prehistoric man

0:14:27 > 0:14:30regarded the place with tremendous awe.

0:14:30 > 0:14:33For all around me, on the lip of the gorge here,

0:14:33 > 0:14:36there are flint implements strewn among the gravel.

0:14:37 > 0:14:40The people of that time didn't make very elaborate implements.

0:14:40 > 0:14:44Just simple scrapers and arrowheads and knives.

0:14:44 > 0:14:47This, perhaps, was a scraper.

0:14:47 > 0:14:49And here, another one.

0:14:52 > 0:14:56And this, maybe a small knife.

0:14:56 > 0:15:00But all of them unmistakably chipped by human hands.

0:15:00 > 0:15:04But although these implements are so common around here

0:15:04 > 0:15:06you only have to go about a mile away

0:15:06 > 0:15:08and you won't find any at all.

0:15:08 > 0:15:10So it seems almost certain that

0:15:10 > 0:15:12at the time that the waters of the Zambezi

0:15:12 > 0:15:15were thundering and smoking over those cliffs,

0:15:15 > 0:15:18prehistoric man had a large encampment here.

0:15:19 > 0:15:21Why did he select this place?

0:15:21 > 0:15:24Well, maybe he too regarded the falls

0:15:24 > 0:15:27as places of magic and mystery and awe.

0:15:29 > 0:15:31Since ancient man was here,

0:15:31 > 0:15:34many migrating tribes have used the Zambezi

0:15:34 > 0:15:36as a highway into the interior.

0:15:36 > 0:15:39The most primitive of the people

0:15:39 > 0:15:42living in the valley today are the Batonka.

0:15:42 > 0:15:46Until recently, the outside world had touched them very little.

0:15:46 > 0:15:50Even now, the women, who seldom go far from their villages,

0:15:50 > 0:15:52still follow their traditional way of life.

0:15:52 > 0:15:55A Batonka girl, to look her best,

0:15:55 > 0:15:58must anoint her body with red ochre.

0:15:58 > 0:16:02She must wear heavy brass anklets and bracelets.

0:16:02 > 0:16:04She must mat her hair with fat,

0:16:04 > 0:16:06and decorate it with beads

0:16:06 > 0:16:09and a little circlet of cowrie shells,

0:16:09 > 0:16:12traded up from the coast hundreds of miles away -

0:16:12 > 0:16:14a coast she has never seen.

0:16:16 > 0:16:19THEY SPEAK IN THEIR OWN LANGUAGE

0:16:19 > 0:16:23Through her nose, she must wear a length of straw

0:16:23 > 0:16:27and many of the older women still smoke curious calabash pipes.

0:16:27 > 0:16:31THEY SPEAK IN THEIR OWN LANGUAGE AND LAUGH

0:16:31 > 0:16:36During the initiation rites, all Batonka girls are disfigured

0:16:36 > 0:16:39by having their two front teeth knocked out,

0:16:39 > 0:16:43which gives even the young women an unnaturally aged look.

0:16:49 > 0:16:52THEY SPEAK THEIR OWN LANGUAGE

0:16:55 > 0:16:57As the dry season advances,

0:16:57 > 0:17:01most of the creeks and swamps that flank the river dry out.

0:17:01 > 0:17:04And many water-living creatures are stranded,

0:17:04 > 0:17:06so that the mud pans are littered

0:17:06 > 0:17:10with shrivelled bodies, such as this of a freshwater crab.

0:17:12 > 0:17:15But some animals have special devices

0:17:15 > 0:17:19which enable them to survive until the next rains.

0:17:23 > 0:17:25This frog, called xenopus,

0:17:25 > 0:17:27manages to prevent being dried to death

0:17:27 > 0:17:30by burrowing deep into the mud as the waters fall.

0:17:31 > 0:17:33Below ground, it can remain alive,

0:17:33 > 0:17:37for there, except in the worst droughts, the earth is still moist.

0:17:37 > 0:17:39It's an odd-looking creature,

0:17:39 > 0:17:41rather like an ordinary frog that's been squashed flat.

0:17:41 > 0:17:44And it has the very un-froglike characteristic

0:17:44 > 0:17:46of claws on its hind legs.

0:18:01 > 0:18:04But one creature has a much more complicated device

0:18:04 > 0:18:07for survival than xenopus.

0:18:07 > 0:18:10At the bottom of this burrow is a hard,

0:18:10 > 0:18:14almost leathery object with a tiny hole in the centre.

0:18:16 > 0:18:20The mud beneath is still slightly moist.

0:18:20 > 0:18:24So it's possible to crack it open and reveal the strange object

0:18:24 > 0:18:27that lies cocooned at the bottom of the burrow,

0:18:27 > 0:18:31shrouded in a crinkled, parchment-like skin.

0:18:45 > 0:18:48If you want to see what is within the cocoon,

0:18:48 > 0:18:52we can persuade it to hatch by putting it in water.

0:18:53 > 0:18:56It then behaves as though the rains have come

0:18:56 > 0:18:59and its swamp has once more become submerged.

0:18:59 > 0:19:03For an hour or so, bubbles appear at the little hole at the top.

0:19:03 > 0:19:08And then, the cocoon begins a series of convulsive shudders.

0:19:09 > 0:19:12Slowly, it loses its outer hard skin,

0:19:12 > 0:19:15which is, in fact, formed of dried mucus.

0:19:19 > 0:19:22Then, at last, a head appears.

0:19:28 > 0:19:31This, in fact, is a lungfish -

0:19:31 > 0:19:34a fish that can live and breathe out of water

0:19:34 > 0:19:39and can survive completely dried up in its cocoon for up to four years,

0:19:39 > 0:19:41without eating anything.

0:19:42 > 0:19:47When it first emerges, its eyes are milky and it seems to be blind.

0:19:47 > 0:19:50It'll be several days before it regains its sight.

0:19:51 > 0:19:53While it was cocooned,

0:19:53 > 0:19:57it lived by absorbing its muscle tissues.

0:19:57 > 0:20:00And after being dried up for a particularly long period,

0:20:00 > 0:20:03a fish may have consumed almost half its original weight.

0:20:08 > 0:20:11The changes necessary in its body chemistry

0:20:11 > 0:20:15to enable it to digest food again are so complicated

0:20:15 > 0:20:18that it will be a week or so before they're complete,

0:20:18 > 0:20:20and it can eat normally once more.

0:20:22 > 0:20:26But when they do start feeding, they put on weight fast,

0:20:26 > 0:20:30for they're aggressive creatures with a very powerful bite,

0:20:30 > 0:20:32and they can grow up to three feet long.

0:20:40 > 0:20:45There are few creatures whose lives are not governed by the water supply,

0:20:45 > 0:20:48and none are more dependent on it than the big game

0:20:48 > 0:20:52wandering across the hot, open plains of central Africa.

0:20:52 > 0:20:56The herds of wildebeest come down every day to the water holes,

0:20:56 > 0:21:00usually in the mornings and again in the evenings,

0:21:00 > 0:21:06their lives one constant trek from pastures to the water and back again.

0:21:06 > 0:21:09The daily procession is a marvellous sight,

0:21:09 > 0:21:12and if you can find a reasonably concealed position,

0:21:12 > 0:21:14with the wind blowing in your face

0:21:14 > 0:21:18so that the approaching animals can't catch your scent,

0:21:18 > 0:21:20then you may sit there all day

0:21:20 > 0:21:23as the herds queue up to take their turn to drink.

0:21:26 > 0:21:32With these wildebeest came a family of warthogs - bold, cheeky creatures

0:21:32 > 0:21:36who will barge their way through any antelope to get to the water.

0:21:49 > 0:21:54The loveliest of the antelopes on the Zambezi must surely be the sable.

0:21:54 > 0:21:57In Kenya and Uganda, the sable is so rare

0:21:57 > 0:22:01that catching sight of one is something to talk about for days.

0:22:01 > 0:22:03But the Zambezi is their homeland,

0:22:03 > 0:22:06and here, these splendid, heraldic creatures

0:22:06 > 0:22:12come down to the water holes in herds up to a hundred strong.

0:22:12 > 0:22:15This male is chasing a reluctant female

0:22:15 > 0:22:18who apparently doesn't welcome his attentions.

0:22:39 > 0:22:45The sable, wherever they go, are accompanied by tick-birds.

0:22:45 > 0:22:47And when the antelope come down to drink,

0:22:47 > 0:22:50the tick-birds sometimes hop off their hosts

0:22:50 > 0:22:52and take a drink themselves.

0:22:53 > 0:22:56Often, too, they move onto other animals,

0:22:56 > 0:22:59so that the water hole is a sort of railway junction

0:22:59 > 0:23:01for tick-bird passengers,

0:23:01 > 0:23:04where they can change from one conveyance to another.

0:23:13 > 0:23:17Here comes the male sable again to claim a place at the water.

0:23:22 > 0:23:25Eland, the biggest of all the antelope.

0:23:25 > 0:23:28They, too, bring tick-birds down with them.

0:23:38 > 0:23:40The tick-birds are of service to their hosts

0:23:40 > 0:23:44by eating not only cattle ticks which may infest the animals

0:23:44 > 0:23:47but also by removing other insect pests.

0:23:47 > 0:23:52Most beasts submit to their attentions uncomplainingly,

0:23:52 > 0:23:55though one can't help feeling it must be extremely irritating

0:23:55 > 0:23:58to have a bird crawling not only into your ear,

0:23:58 > 0:24:00but right over your eye.

0:24:07 > 0:24:10But the birds are something of a mixed blessing,

0:24:10 > 0:24:13for often if an animal has a wound or a sore,

0:24:13 > 0:24:17then it's precisely here that flies will lay their eggs,

0:24:17 > 0:24:18and here that the tick-birds

0:24:18 > 0:24:21will therefore find their richest meal of grubs.

0:24:21 > 0:24:25But because they peck so continuously at the sores

0:24:25 > 0:24:29they often keep them open long after they would otherwise have healed.

0:24:29 > 0:24:32But, whether the animal appreciates the bird or not,

0:24:32 > 0:24:36there is little any of them can do to rid themselves of their guests.

0:24:53 > 0:24:56Although the middle of the Zambezi remained unexplored

0:24:56 > 0:24:59until Livingstone came here a century ago,

0:24:59 > 0:25:02the mouth of the river was well known to the Portuguese,

0:25:02 > 0:25:07who by the 15th century had mapped the coast with astonishing accuracy.

0:25:09 > 0:25:12Vasco da Gama skirted round the continent

0:25:12 > 0:25:14on his way to India in 1497.

0:25:14 > 0:25:18He sailed up the east coast and landed,

0:25:18 > 0:25:22but the local people attacked him, so he didn't stay long.

0:25:22 > 0:25:27Nevertheless, East Africa was now open to European exploitation.

0:25:29 > 0:25:32The Portuguese were soon back in force,

0:25:32 > 0:25:35and this time they came to stay,

0:25:35 > 0:25:38for from here they could control a sea route to India.

0:25:39 > 0:25:43Where they could, they made treaties with the local chiefs.

0:25:43 > 0:25:46Everywhere they built forts.

0:25:46 > 0:25:51Between 1505 and 1507, working from their base on Mozambique Island,

0:25:51 > 0:25:54they erected a network of fortifications

0:25:54 > 0:25:56around the coast and up the rivers.

0:25:57 > 0:26:00Some of the forts still stand to this day,

0:26:00 > 0:26:05like this one at Tete on the Zambezi 200 miles up the river.

0:26:13 > 0:26:15None of them are big,

0:26:15 > 0:26:19just simple rectangular strongholds 100 yards or so square,

0:26:19 > 0:26:22which, in times of trouble,

0:26:22 > 0:26:25could house a garrison of a few hundred men.

0:26:25 > 0:26:28All are heavily fortified with thick stone walls

0:26:28 > 0:26:30which were easily proof

0:26:30 > 0:26:33against the arrows and spears of the local people.

0:26:37 > 0:26:40Cannonballs still litter these ramparts,

0:26:40 > 0:26:44and indeed, in the 16th century, the Portuguese had to be well armed

0:26:44 > 0:26:47and had real need of these fortress walls,

0:26:47 > 0:26:50for there was more or less continuous battle and warfare

0:26:50 > 0:26:52with the local African tribes.

0:26:52 > 0:26:55Again and again, the Portuguese settlements were overrun

0:26:55 > 0:26:56and all the inhabitants slaughtered.

0:26:56 > 0:27:00But the rewards for staying here were great.

0:27:00 > 0:27:04For one thing, there were slaves to be captured and taken down river

0:27:04 > 0:27:07to be sold in the great markets of the east coast of Africa.

0:27:07 > 0:27:08And then there was ivory.

0:27:08 > 0:27:12300 years ago, no part of Africa was richer in elephant

0:27:12 > 0:27:15than this part of the lower Zambezi.

0:27:15 > 0:27:18And across the Indian Ocean in the Portuguese colony of Goa,

0:27:18 > 0:27:21the craftsmen were clamouring for ivory.

0:27:21 > 0:27:24But above all, there was gold.

0:27:24 > 0:27:28Away to the south lay a great African kingdom,

0:27:28 > 0:27:30the kingdom of Monomotapa,

0:27:30 > 0:27:33and from it came a steady trickle of gold.

0:27:33 > 0:27:35The Portuguese were sure that there was much more down there,

0:27:35 > 0:27:39because down there, they believed, lay King Solomon's mines.

0:27:39 > 0:27:43And the Arabs, who came up from the south,

0:27:43 > 0:27:46brought stories of a great stone city that was rich in gold.

0:27:46 > 0:27:51DRUMBEATS

0:27:54 > 0:27:58Such a golden city really did exist away to the south,

0:27:58 > 0:28:00although it's unlikely that the Portuguese ever reached it.

0:28:00 > 0:28:03Indeed, it wasn't until the end of the 19th century

0:28:03 > 0:28:07that men from the outside world set eyes on this,

0:28:07 > 0:28:10the citadel of Great Zimbabwe.

0:28:21 > 0:28:26By the 19th century, the existence of the kingdom of Monomotapa

0:28:26 > 0:28:28had largely been forgotten, and no-one could believe

0:28:28 > 0:28:32that these astonishing ruins were the work of an African people.

0:28:32 > 0:28:36After all, the local tribesmen built only simple mud huts.

0:28:36 > 0:28:38How could they ever have understood

0:28:38 > 0:28:41the complicated technique of building in stone?

0:28:41 > 0:28:45And so, to explain these ruins, some fanciful antiquaries

0:28:45 > 0:28:48remembered once more the stories of King Solomon's mines.

0:28:48 > 0:28:50Perhaps these were they,

0:28:50 > 0:28:54or maybe this was the golden city of Prester John.

0:28:54 > 0:28:56Some felt certain it was a fortress built perhaps

0:28:56 > 0:28:592,000 years ago by the Phoenicians.

0:28:59 > 0:29:02And others, recalling the pinnacle towns on the Red Sea,

0:29:02 > 0:29:05suggested that it might have been built by Arabs.

0:29:08 > 0:29:10But one thing was certain,

0:29:10 > 0:29:14whoever had built Zimbabwe was certainly rich in gold.

0:29:14 > 0:29:16The first European visitors to the place,

0:29:16 > 0:29:19perhaps with the thoughts of King Solomon's mines

0:29:19 > 0:29:24fresh in their mind, ransacked the place in search of gold.

0:29:24 > 0:29:27There was even a company set up to seek for treasure.

0:29:27 > 0:29:30It was called the Ancient Ruins Company Ltd.

0:29:30 > 0:29:32One man, by his own admission,

0:29:32 > 0:29:37took out over £4,000 worth of gold from these ruins.

0:29:37 > 0:29:40And even today, after the rains of the wet season

0:29:40 > 0:29:42have washed away another layer of earth,

0:29:42 > 0:29:45sometimes you can pick up little golden beads

0:29:45 > 0:29:47or little blocks of gold.

0:29:48 > 0:29:50Like these.

0:29:52 > 0:29:56Today, much of the mystery that once shrouded Zimbabwe

0:29:56 > 0:29:57has been unravelled.

0:29:57 > 0:30:01Systematic excavations by archaeologists have shown

0:30:01 > 0:30:04that this was once the capital and the ritual centre

0:30:04 > 0:30:06of a great African kingdom

0:30:06 > 0:30:09that reached its heyday about the 15th century.

0:30:11 > 0:30:13There are signs that this rock mountain

0:30:13 > 0:30:16was inhabited from the earliest times,

0:30:16 > 0:30:20but it wasn't until about 1100AD that the people living here

0:30:20 > 0:30:23invented the curious and individual style of building

0:30:23 > 0:30:25that's characteristic of Zimbabwe.

0:30:25 > 0:30:28They began to improve the shelter provided by the granite boulders

0:30:28 > 0:30:32by laying lines of stone walls on the rocks themselves

0:30:32 > 0:30:34without cement of any sort.

0:30:34 > 0:30:37And they continued to develop and improve their technique

0:30:37 > 0:30:40during the next 300 or 400 years.

0:30:40 > 0:30:45During that time, 15,000 tonnes of granite were knocked into shape

0:30:45 > 0:30:48and carried up the hill to construct these walls.

0:30:48 > 0:30:50But what was this place,

0:30:50 > 0:30:54and why was it built so laboriously on the top of the hill?

0:30:54 > 0:30:55Judging from what we know

0:30:55 > 0:30:58of the rituals and beliefs of other African people,

0:30:58 > 0:31:02it seems certain that Zimbabwe was a highly sacred place,

0:31:02 > 0:31:07a sanctuary inhabited by a king who was almost a god.

0:31:07 > 0:31:08Such a being was so sacred

0:31:08 > 0:31:11that he was shut away from the eyes of his people.

0:31:11 > 0:31:14It's unlikely that any common folk

0:31:14 > 0:31:17were allowed to come up to this hilltop citadel.

0:31:17 > 0:31:19They waited in the valley below

0:31:19 > 0:31:23while sacrifices were being made up here in the temple.

0:31:26 > 0:31:29Along these narrow stone corridors,

0:31:29 > 0:31:33the divine king would once have made his way to perform the rituals

0:31:33 > 0:31:36believed necessary to bring rain after drought

0:31:36 > 0:31:38or to ensure the fertility of the land.

0:31:44 > 0:31:46And from this position up here

0:31:46 > 0:31:51it's possible that the priests, unseen, spoke to the people.

0:31:51 > 0:31:54For these huge granite boulders around me

0:31:54 > 0:31:57produce the most extraordinary acoustical effects.

0:31:57 > 0:32:01And it's quite possible for a man standing here

0:32:01 > 0:32:04to speak in a normal voice and be heard and understood

0:32:04 > 0:32:08in the great enclosure across the other side of the valley

0:32:08 > 0:32:09half a mile away.

0:32:11 > 0:32:13Down there in the valley,

0:32:13 > 0:32:17it's still an eerie experience

0:32:17 > 0:32:22to hear a voice come floating down to you from the sky.

0:32:26 > 0:32:31This impressive wall of the great enclosure down in the valley

0:32:31 > 0:32:34was constructed somewhat later than the buildings on the hill.

0:32:35 > 0:32:38When the masons began to erect the gigantic wall,

0:32:38 > 0:32:41at this point, their technique was at its most refined.

0:32:41 > 0:32:44Here the stonework is laid in narrow courses,

0:32:44 > 0:32:47beautifully regular and elegantly shaped.

0:32:47 > 0:32:49The granite was quarried from the hillside,

0:32:49 > 0:32:52and the labour involved must have been immense.

0:32:52 > 0:32:54There's as much masonry in this one wall

0:32:54 > 0:32:57as in the whole of the hilltop buildings put together.

0:32:57 > 0:32:59But it seems that, as the work proceeded,

0:32:59 > 0:33:02the masons lost heart in their enterprise,

0:33:02 > 0:33:04for as they worked their way around the wall,

0:33:04 > 0:33:07which at its beginning is over 30 feet high,

0:33:07 > 0:33:09it becomes lower and the workmanship less fine.

0:33:23 > 0:33:26And here, where so many of the passages

0:33:26 > 0:33:28inside the great enclosure converge,

0:33:28 > 0:33:31and where I can look through one of the gateways

0:33:31 > 0:33:34straight across the valley to the holy of holies up on the hill,

0:33:34 > 0:33:37is this big platform of stone.

0:33:37 > 0:33:38When it was first discovered,

0:33:38 > 0:33:41it was buried beneath a lot of decaying leaves.

0:33:41 > 0:33:43But when they cleared the rubbish away,

0:33:43 > 0:33:47they found that on top of it were a large number of ox bones

0:33:47 > 0:33:50and a great quantity of charcoal.

0:33:50 > 0:33:53It seems certain, in fact, that this was an altar

0:33:53 > 0:33:57on which sacrifices of oxen were made to propitiate the rain god.

0:33:58 > 0:34:03So this was the palace of the king of Monomotapa,

0:34:03 > 0:34:07built by Africans about 500 years ago.

0:34:11 > 0:34:13But although, through the work of archaeologists,

0:34:13 > 0:34:17we now know so much about Zimbabwe, about who built it,

0:34:17 > 0:34:20when it was built and what it was used for,

0:34:20 > 0:34:22there are still a lot of unsolved mysteries here,

0:34:22 > 0:34:26and not the least of them is this tower.

0:34:27 > 0:34:29At the end of the 19th century,

0:34:29 > 0:34:31one investigator, perhaps in search of gold,

0:34:31 > 0:34:34tried to tunnel down from the top in case it was hollow,

0:34:34 > 0:34:36but he found nothing but rubble.

0:34:36 > 0:34:41Later on, a trench was dug beneath it to see if there was anything there.

0:34:41 > 0:34:42They found nothing.

0:34:42 > 0:34:46And so it remains a total enigma.

0:34:46 > 0:34:49Zimbabwe still guards some of its secrets.

0:34:50 > 0:34:54RAPID DRUMBEATS

0:35:08 > 0:35:12MACHINERY RUMBLES AND BUZZES

0:35:30 > 0:35:36In 1955, engineers and mechanics, geologists and construction workers

0:35:36 > 0:35:39descended into the Zambezi Valley

0:35:39 > 0:35:41at a place where the river wound its way through a gorge

0:35:41 > 0:35:44which the local people called the Trap.

0:35:52 > 0:35:54Here, the newcomers built

0:35:54 > 0:35:58the most impressive construction since Zimbabwe -

0:35:58 > 0:35:59the Kariba Dam.

0:36:08 > 0:36:10Behind the huge, curving wall

0:36:10 > 0:36:14stretches the largest man-made lake in the world,

0:36:14 > 0:36:17which flooded the valley for over a hundred miles upstream.

0:36:18 > 0:36:23Water now covers land that once was parched desert and desolate scrub.

0:36:24 > 0:36:26Whole forests were drowned.

0:36:28 > 0:36:32Herds of hippopotamus now swim above the country

0:36:32 > 0:36:35where once the Batonka planted their cassava.

0:36:40 > 0:36:44The bulls open their vast jaws in what looks like a yawn

0:36:44 > 0:36:47but is more probably a display of their might to the rest of the herd.

0:37:07 > 0:37:10Out on the lake, the Batonka are given lessons

0:37:10 > 0:37:13by government-trained instructors.

0:37:13 > 0:37:18For these people, resettled on the shores of the vast new lake,

0:37:18 > 0:37:19had no traditional knowledge

0:37:19 > 0:37:22of how to exploit the riches on their doorsteps.

0:37:22 > 0:37:26And so the techniques of fishing in deep water with nets

0:37:26 > 0:37:27had to be explained to them.

0:37:27 > 0:37:32MEN CHATTER IN THEIR OWN LANGUAGE

0:37:34 > 0:37:37The harvest they reap is indeed a rich one -

0:37:37 > 0:37:41catfish, bream, tiger fish, and all of them good eating.

0:37:42 > 0:37:46The fish inspectors note carefully the weight of the yield

0:37:46 > 0:37:47and the types of fish

0:37:47 > 0:37:50so that the biological progress of the lake can be charted.

0:37:50 > 0:37:52- 23. - 23.

0:37:55 > 0:37:59Many of the Batonka men had worked on the building of the dam

0:37:59 > 0:38:02and had learned the ways of the outside world,

0:38:02 > 0:38:04so most of them now wear European clothes.

0:38:04 > 0:38:09But the women, whose job it is to gut and scale the fish,

0:38:09 > 0:38:12have still remained secluded in their villages,

0:38:12 > 0:38:16and they are still dressed as they've always been.

0:38:16 > 0:38:18WOMEN CHATTER

0:38:21 > 0:38:23The engineers of Kariba

0:38:23 > 0:38:27control not only life upriver but downriver as well,

0:38:27 > 0:38:30for by the operation of the floodgates

0:38:30 > 0:38:32they can bring drought or flood

0:38:32 > 0:38:34to the people farther east in Mozambique.

0:38:49 > 0:38:54And so the Zambezi approaches the end of its 2,000-mile journey.

0:38:54 > 0:38:58It began as a tiny stream in the heart of Africa.

0:38:58 > 0:39:01Its water has given life to the herds of elephants

0:39:01 > 0:39:03and antelope that browse along its banks

0:39:03 > 0:39:07and abundant fish to the people who live beside it.

0:39:07 > 0:39:10The Portuguese and the explorers who came after them

0:39:10 > 0:39:12used it as a highway to the interior,

0:39:12 > 0:39:15and modern man has harnessed its waters

0:39:15 > 0:39:17to bring power to central Africa.

0:39:17 > 0:39:20But now the river is old.

0:39:20 > 0:39:22It drops its burden of sand and silt

0:39:22 > 0:39:26in a series of sandbanks that clog its mouth.

0:39:26 > 0:39:28It meanders sluggishly on,

0:39:28 > 0:39:32threading its way between the sandy islets of its estuary

0:39:32 > 0:39:34until it reaches the coast.

0:39:34 > 0:39:39And then, at last, it loses itself in the Indian Ocean.

0:39:39 > 0:39:42PERCUSSIVE DRUMBEATS AND AFRICAN CHANTING

0:39:42 > 0:39:45SOLO MALE VOICE CHANTS

0:39:52 > 0:39:56MASSED VOICES JOIN IN CHANT