A Very British Map: The Ordnance Survey Story Timeshift

The Ordnance Survey has steadfastly mapped our lives for over 200 years.

During its long history, the OS has produced billions of maps...

..meticulously recording every square mile of our nation.

All 94,525 of them.

For me the Ordnance Survey embodies everything

that is best about being British -

the attention to detail,

the pioneering expeditionary fervour

that went into the initial surveying...

..and the continuing expertise that makes these maps

the best in the world.

Every city, village and town,

every street and every house has been mapped

by an army of boffins and intrepid adventurers.

Whatever it took.

We had no health and safety, no helmets.

We used to wear wellingtons so that you could put your spanners in.

It was like the Wild West, you know what I mean?

It's a triumph of great British design

and no-nonsense practicality...

OS 12 to OS 13,

will you move to the corner of the barn, please.

'I think you'll have to shoo the cattle out of the way, over.'

..and tireless dedication.

One side of an outdoor leisure map took two years.

Produced with such loving craft, the OS map has become our trusted guide,

ever ready to show the way to generations of holiday-makers,

weekend adventurers and ramblers.

VOICEOVER: As for maps, you can't beat the Ordnance Survey.

They're absolutely reliable and show all those off-the-highway haunts

the true rambler loves to explore.

After mapping the changing contours of the nation's life

through the decades,

now in the digital age of Sat Nav,

interactive and 3-D maps,

the OS is having to change itself.

But the Great British public's enduring love affair

with the humble foldout OS map is still alive and well.

If you go three steps outside your front door, that will be on a map.

You know, what other country can do that?

If you've ever ventured into the great outdoors,

chances are there's been an OS map stuffed in the rucksack.

We used to go on family holidays to a beautiful

part of the Yorkshire Dales

from about the age of six months upwards

and I remember very clearly when I was about eight,

my stepfather spreading an ordnance survey map

out over the dining room table in the cottage that we were staying in

and explaining to me the walk that we were going to do later that day.

To me, it was like being taught how to crack a code,

suddenly learning how to decipher all of these symbols,

these contour lines

and how to translate them into an image of the landscape itself.

My earliest memory is being shown how to use this

Ordnance Survey map, Sheet 126, by my parents,

who kept it among many other OS maps

on their bookshelves at home.

With this sheet here, I was able to go out into the countryside

of Norfolk on my bicycle, or on foot,

exploring public rights of way.

The public footpaths, the public bridleways, all those routes that

are not Tarmac and are therefore THE most exciting ones to explore.

Do you need a map? OK, Beth, there's your map.

There are two series of Ordnance Survey maps used by walkers.

Still out and about at the age of 83, Hugh Westacott is

a poster boy for the benefits of a lifetime's rambling.

And we are in lowland countryside...

Today he's guiding a group of walkers to Coombe Hill

on the edge of the Chilterns in Buckinghamshire.

There are 140,000 miles

of public paths in England and Wales.

There are more miles of footpath

than there are roads

but we are actually going to walk

along the top of a very steep escarpment.

If you look at those contour lines, it's very, very steep.

Is everybody ready to move off now?

And you know what we're looking for?

A steep hill down.

OK.

For over 70 years, the Ordnance Survey has taken Hugh the length

and breadth of Britain and it's never failed him.

I've walked from Land's End to Fort William relying

entirely on Ordnance Survey maps.

They're so remarkably accurate.

Because they're so accurate, it makes it easy to follow.

We're standing now at the viewpoint on the top of Coombe Hill,

which is probably one of the most striking views in the Chilterns.

You can see for hundreds of square miles.

I couldn't imagine England without Ordnance Survey.

It's one of our great treasures.

They're very handsome, they really are.

They're works of art.

I'm a dinosaur.

I much prefer paper maps to using GPS receivers

because the difficulty with the GPS is the screen that you look at is

so limited, you can't see the bigger picture.

Over more than 200 years of development...

..the maps have become a masterpiece of clarity and precision.

Ordnance Survey maps are probably the easiest

maps in the world to read.

They're very simple.

They have a very harmonious set of colours on them

that accord with psychologically the way

we need to absorb information.

For example, the big roads,

the dangerous bits are bright red.

The rivers are blue.

The woods are green.

There's a logic to the colour system,

so you're given a lot of help when you're using an Ordnance Survey map.

Among true devotees of the OS map, most agree that the

absolute pinnacle of the cartographer's art

is the 1 to 50,000 scale Landranger map.

In this series, the whole country is divided

up into 204 different sheets.

One kilometre of Britain

is represented by 2cm on the map.

For most of the history of the OS,

nearly everything on the map was drawn by hand.

A cartographer's training could take up to a year.

I started in the drawing school and I did practising drawing

and putting names onto maps.

Then after one year

I did a final drawing test, completed that

and then I was transferred to a large-scale drawing section.

I worked on very large-scale maps.

You drew the detail, you drew the rivers, you drew the cliffs

and the gravel pits and the railways

and the shores and the bogs.

All this detail came from years of the laborious legwork and

meticulous measuring done by the Ordnance Survey's men in the field.

VOICEOVER: Now to fill in the details.

Mark the starting points for the survey of side roads,

check the positions of fences and the fronts of houses.

One of the things that any surveyor out in the field had to find out

to put on the map was the names of places

and this caused all kinds of kerfuffle.

There is a wonderful field guide for surveyors

that they issue and they tell them in strict order

who they should believe for names.

It starts with clergyman and schoolmasters and doctors

and goes down, down, down the list

and then it says uncategorically don't believe the people who

live in the houses themselves, especially if they are labourers

or kind of common, basically, because they won't have a clue,

especially they won't have a clue how to spell it.

Once all the names had been spelt correctly, the surveyor's map

was then turned into the final work by the cartographer

on zinc plates.

The plates were then photographed and maps printed from the negative.

In the '50s and '60s, the men in the field were just that - men.

In the drawing sections, it was an admirably modern-looking workplace.

And almost alone among British institutions at the time,

the OS recognised this in the employees' salaries.

One of the big bonuses was that we were actually on equal pay

with the men.

We were treated equally.

There was a small problem in that not many girls were very good

at sharpening their drawing pens and

so you had to talk nicely to one of the men

to sharpen your drawing pen.

I could never do mine, I always had to rely on somebody else

because it was, at that time, it was more of a man's technical thing.

Once Marilyn's pen was properly sharpened,

she loved some of the symbols she had to draw.

They included bus stations,

churches, wind pumps

and Marilyn's favourite - rubbish dumps.

You would start with little tiny boulders

and you would draw the bigger boulders at the top

and then it would go down to give the impression

of a heap of rubbish, or refuse.

Did I get it right?

Was it the little ones at the top, or the big ones?

-No, the big ones at the top...

-Yeah.

-..becoming little dots towards the bottom.

-Yeah.

The draughtsmen and women who sweated over every last rock

of the rubbish dump were the unsung heroes of the OS map.

Their handiwork went uncredited,

so they found ways of leaving their mark.

The draughtsman, for all the work he's done,

never got his name on his pieces of work. We all did, of course.

We were quite ingenious at finding ways of signing the thing

and concealing it in the detail

but anybody who knows where to look

will find a lot of the draughtsmen's names in there.

On a cliff face was a great camouflage.

Such mischief on the map was normally spotted.

The survey's military attention to detail meant that there

was absolutely no room for error for the backroom men and women.

First of all, it was examined by your immediate supervisor.

It was then examined by his senior

and then it left and went to a section

which was devoted entirely to examining things.

That's what these guys did and they were all military people.

They examined everybody's maps and tore them to shreds

and then you were called over to put everything right.

It was very strict in those days, you were called by your surname

and there was no walking around in shirt sleeves.

It was that sort of environment.

You had old, um, almost Edwardian type

schoolmaster figures who ran the sections

and it just felt like being at school again sometimes.

This highly-disciplined working environment is

entirely in keeping with the origins of the Ordnance Survey,

which date back to the 1790s and the threat of Napoleonic invasion.

The Board of Ordnance was tasked with drawing up accurate maps

of the south coast of England to defend the nation.

Based in the Tower of London,

the Board of Ordnance looked after artillery, transport and supplies.

To complete the mapping,

the Board turned to cutting-edge technology

and the most precise piece of measuring equipment the world

had ever known -

the theodolite.

This is a five-inch theodolite

and the five-inch

refers to the size of these scales.

This is the vertical scale,

runs around here

and inside the base is the horizontal scale.

Both scales are calibrated in degrees, minutes and seconds

and can be read through these very fine microscopes here.

It has levelling bubbles to get the instrument precisely level,

to ensure accuracy when reading the angles again and again.

After the surveyors had measured the distance between

two points on the ground,

a theodolite was used to calculate

the angles to a third point.

Using the laws of geometry,

the distances to each point

were then calculated.

These are really skilled operators.

Even the booking of the readings you're given

has to all be done by hand

and all the calculations afterwards done by hand

using log tables and the like.

Yes, a lot of skill required.

In charge of the mapping of Kent was William Mudge.

Between 1798 and 1820,

he was the Ordnance Survey's first superintendent.

He's a brilliant figure

because he's both an administrator,

a kind of good politician,

but he's also a practical surveyor.

He's a real sort of child of the Enlightenment -

he gets the idea that you need to believe

in the idea of rational, mathematical thinking

to create objective maps.

Mudge's ground-breaking map of Kent,

on a scale of one inch to the mile,

was published in January 1801.

He's the figure who sort of really establishes the Ordnance Survey

as a long-term rolling project

which is given validation by the state

and also begins to have a wider popular, public impact.

So Mudge, I think, is the great hero, really, of the early days of the Ordnance Survey.

From this southern starting point,

Mudge's successor Major General Thomas Colby mapped his way

further up England and Wales between 1820 and 1847.

Colby was extremely eccentric, very, very energetic.

A complete workaholic, really.

He only had one hand, which was a huge hindrance for a surveyor,

and that had happened on an earlier training exercise where

he had been shown a pair of pistols which had then gone off in his hand.

He had to manage this incredibly delicate surveying equipment

with only one hand to do so.

Under his guardianship,

the Ordnance Survey finished publishing the first series of maps.

That series was officially finished in 1873

with the last map published of the Isle of Man.

The mapping of Britain, inch by painstaking inch,

took over 70 years.

Given the technology of the time, this was a colossal achievement.

Each map was the equivalent of two days' average wages,

putting them out of reach for most citizens.

But in time, the OS did come to realise the possibilities

for a more widespread usage of its maps among civilians.

By the turn of the 20th century,

the Ordnance Survey had mapped the whole of the British Isles

but with its hefty price tag, the print run of each map

remained very limited, with never more than 1,000 prints.

They weren't straightforward to get hold of around 1900.

You could get them through booksellers

and the booksellers then had to get them through

a central agent in London

who got them from Ordnance Survey themselves.

The British landscape had changed by the early 1900s.

The age of the motor car had opened up the country like never before.

Commercial map-makers spotted a gap in the market for the new traveller.

None more so than the Edinburgh company Bartholomew.

This canny Scottish firm started issuing half-inch maps entirely

based on OS one-inch maps entitled simply Reduced Ordnance Survey Map.

Bartholomew's took the OS map, added more attractive colours,

and they were soon flying off the shelves.

This shameless plagiarism didn't go down well with

the gentlemen of the Ordnance Survey.

It was suddenly realised that there was quite a bit of money

to be made out of copyright

and that is when rumblings began

from the Ordnance Survey in Bartholomew's direction.

John Bartholomew complained mightily,

called the whole thing ungentlemanly,

and had to change the title of his half-inch series

from Reduced Ordnance Map to just Reduced Map,

and you can see the change on this in the covers.

The 1911 Copyright Act enabled the Ordnance Survey to control

the reproduction of its maps by others much more effectively.

From this time on,

the words Crown Copyright Reserved were included on all its maps.

With this new commercial confidence came a new director-general.

Charles Close was determined to transform the Ordnance Survey

into a modern, popular mapping company.

He thought that Ordnance Survey mapping could be rationalised,

more particularly the small-scale mapping -

they could be greatly improved in appearance.

Close, like all heads of the Ordnance Survey up to 1977,

was a soldier, a Royal Engineer, and he wanted to improve the mapping

also from the point of view of military functionality.

The outbreak of World War I

disrupted Close's big plans for updating the covers.

But it allowed him to put the maps to vital military use.

The significance of the Ordnance Survey

was that it provided a nucleus of trained military

and civil manpower

who could be used both for surveys and for drawing and printing maps.

The OS planned to produce the maps at Southampton

and then ship them to France.

It becomes apparent that more sophisticated warfare

which has developed elsewhere is going to happen here,

with invisible firing, not from guns, of a dug-in enemy,

and therefore you need to survey in where they are.

The OS experts devised ingenious methods of surveying enemy lines...

..one of which was from the air.

Captain Harold Winterbottom was put in charge of the aerial division.

He was tasked with spotting

and photographing German artillery positions.

On the ground, observers had his plane firmly in sight.

At the moment when the target's position was received,

the telescope would be clamped and the bearing read off.

Winterbottom's strike rate was so phenomenally accurate

that British artillery troops called him The Astrologer.

When the war finally ended on November 11, 1918,

the Ordnance Survey had produced an astonishing 33 million maps

and diagrams for the British Army.

Quite a lot of this would involve getting as close to enemy lines

as possible, and even though they were wearing tin hats,

they would still be likely to be shot at.

67 men and women lost their lives

serving the Ordnance Survey during the conflict.

With the end of the war, Charles Close returned

to his plans for the modernisation of the Ordnance Survey...

..convinced that to survive it needed to generate

an income from its sales.

Prewar, the Survey's rivals made a small fortune with tourist maps,

cheekily using Ordnance Survey data.

Now, Charles close wanted a piece of this lucrative market.

In 1919, he launched a new set of one-inch tourist maps

aimed squarely at the holiday-maker.

The OS was quite deliberately going down-market.

The die-hard colonels and brigadier generals must have thought it

was hideously mimsy and pandering to horrible taste,

but they had to make some money, and that was a way of doing it.

Before the First World War, OS maps were drab, utilitarian objects.

So, to make them more appealing, Close decided to employ

the Survey's first-ever professional artist, Ellis Martin.

Gone were the old buff covers, gone were the old paper covers,

and in their place were introduced a series of pictorial covers,

which revolutionised the whole map marketing area for Ordnance Survey.

Ellis Martin's covers were painterly and picturesque.

They featured people, too,

the types who might buy the maps - pipe-smoking ramblers, cyclists,

and motorists.

Within two years of Ellis Martin joining,

map sales had gone through the roof.

In 1921, the OS recorded the highest-ever map sales.

Profits were up by 56% and Charles Close put this down

to the quality of Martin's cover designs.

While Ellis Martin worked for the Ordnance Survey between the two

world wars, he reigned supreme.

Nobody else matched him as a map cover designer.

Martin's artistic rebranding cleverly coincided

with the zeitgeist of the '20s and '30s.

This was an era which saw increased leisure time

for the lower middle classes.

It turned the stylish OS map into a must-have travel accessory.

-VOICEOVER:

-We are now at the top of Leith Hill,

one of Surrey's most famous beauty spots.

As for maps, you can't beat the Ordnance Survey.

Absolutely reliable, they show all those off-the-highway haunts

the true rambler loves to explore.

The relationship between the accuracy of the Ordnance Survey maps

with the possibilities it allows you of exploring the landscape

plus the heightened nationalism in the interwar period

has really cemented that idea of the Ordnance Survey maps

as an icon of patriotic Englishness.

Since feet are very much in evidence,

footwear is another important consideration,

so choose your boot to suit your route.

Many people's favourite series of OS maps,

known as the Popular Edition, is from this era,

published between 1919 and 1926.

That era spans a part of history in Britain where the number

of motor cars on the road went up from 77,000 to around one million.

And so that map is the last picture we have of Britain

before it was overrun by motor transport.

I am looking at a Britain that no longer exists -

it's a Britain before motorways,

before airports, or at least before many of them.

But it's a Britain before traffic jams.

It's a quiet, a very peaceful Britain.

The Ordnance Survey's maps are an irreplaceable record

of historical change.

Because the OS has been mapping Britain for so long,

you can compare the same place through different ages,

so you get these spot checks of development

through many, many different eras.

In that respect, they are a completely invaluable,

unique resource.

As well as charting historical change,

some OS maps are also highly sought-after.

Certain covers have become very collectable.

There was one map produced in 1927

for the eclipse of the sun.

This map was valid for only one day, but it showed

the path of the sun's eclipse across the country on that day in 1927.

That is quite a collectable map.

There's always been something about Ordnance Survey maps that appeals

to the Great British compulsive, of the outdoor and armchair variety.

These are very collectable items,

something which one can put in a house,

don't take up too much room, and on the whole are a lot cheaper

than a very fine piece of antique furniture.

It is the fellows that generally collect the maps.

Men are completists.

We have that bit of our brain that wants the full collection,

and it doesn't matter whether it's Bob Dylan albums

or stars' autographs, we have to have the full collection.

OS maps are just the same.

Of course, you have a finite number, you have the 204 Landrangers of

the whole country, and for a fellow, the ambition is to get them all.

31-year-old Ed Fielden has been collecting OS maps

for over 12 years now.

I think I probably am a map addict.

It's one of those addictions that I don't think anyone can help.

It's perfectly harmless.

In fact, it's an enriching addiction.

So, I've just moved house

and this is probably the first room I got going properly -

this is what I'm calling my map room, if you like.

There's somewhere in the region of 3,000 maps just in this room,

and a few hundred others in boxes still to be sorted through.

I would probably say that I have spent over £10,000 so far,

collecting all these maps.

But it's money well spent.

The thing I probably like most about Ordnance Survey maps

is their clean lines, their... You know, you feel a sense of accuracy

when you look at a map made by Ordnance Survey.

There's quite a joy in seeing a paper landscape, if you will,

and interpreting that into how it would look on the ground,

and then when you go out with the map,

you see that landscape come to life, in effect.

You see all the bumps and the hills and the various roads

and streams and rivers and all of that, it comes to life.

Most Ordnance Survey maps include a symbol of a small blue triangle

with a dot inside.

This marks a triangulation point.

For map addicts like Ed, these are places of pilgrimage.

I've visited somewhere in the region of 300 trig points so far.

Each time I visit a trig point, I take a little photograph of it,

and I log my visit and make a note of the date and time,

and say when I visited.

I've got about 6,200 pillars to visit yet,

and I think it's going to take me a few years to do it.

The thousands of trig points which cover the length

and breadth of the country were built between 1935 and 1962.

This was one of the hardest and most important projects

undertaken by the Ordnance Survey in the whole of the 20th century.

The original 19th century measurements were out of date

and needed to be revised.

To do this, the OS devised a new metric grid system

which split the country up into squared sections.

Each grid would receive their own map at a new, more detailed scale

of 1:25,000, the equivalent of 2.5 inches to the mile.

In charge of this vast project was Brigadier Martin Hotine.

A veteran of World War I, he was a stickler for accuracy.

His simple idea was to build an extensive system of four foot

concrete observation points across the UK

from which new measurements could be taken.

They were built by members of the Ordnance Survey,

taking sand and cement and plywood formers

to build these things at all of these high points.

They had to make this concrete construction

on top of all of these mountains.

They had very deep foundations, which is one of the reasons

they're all still on mountain tops to this day.

They were built to last.

The OS employed the same principles it had used for their initial

mapping of the country in the 1800s.

-VOICEOVER:

-Theodolites are used to line up the tripods which carry

the measuring tapes.

Microscope readings are taken every 24 metres

until the whole ten-mile baseline is complete.

From this baseline, the OS built up a network of points

which provided a template for the highly precise remapping of Britain.

The most effective way to make accurate measurements

from the new system of trig points

was in the middle of the night, using powerful torch lights.

The surveyors sometimes had to wait days for a clear night to appear.

But the project was disrupted by the outbreak of World War II,

and was not completed until 17 years after the war ended.

Working on its completion was Dave Broadley's first job

when he joined the Ordnance Survey in 1957.

They'd progressed through the country,

and the Outer Hebrides and the north of Scotland

was the last bit to be done.

You would have to carry, as well as the theodolite,

which we called a fiddle because it was fiddly...

And they were heavy. We also had a lamp,

which was a miniature searchlight,

and a six-volt car battery

up a mountain, right?

Which was heavy.

And then you'd have to have maybe a tripod as well to stand it on.

We had to do the readings many, many times.

Measuring flatter areas of England such as East Anglia

was not any easier.

With no convenient hills available,

the surveyors had to erect enormous and rather flimsy steel structures.

They were called Bilby Towers.

On the outside was like a stepladder, and you used to climb up there

and, if you were on your own,

you had to climb up with a six-volt battery in one hand, in a carrier,

and do it like this.

All the way to the top. 103 foot.

We had no health and safety, no helmets.

We used to wear wellingtons so you could put your spanners in.

It was like the Wild West.

We felt like pioneers.

It was an adventure.

I felt privileged to be doing it.

Sorry.

Mmm.

When the re-triangulation project was finally completed,

the mass of new geographical information was used

to make more accurate, up-to-date maps.

-VOICEOVER:

-This printing machine, which was made in Leeds,

will print 5,000 spot-on Ordnance Survey maps an hour.

This colourful world in miniature and minute detail.

By the late 1960s, Britain was being re-forged in the white heat

of a technological and scientific revolution.

The Ordnance Survey was not immune

from big changes to the way it operated.

Machines were beginning to take away many aspects

of the draughtsman's job.

As far back as the late 1940s,

the OS had been using aerial surveys to update its maps.

But the adoption of the stereo plotting machine

had made this much easier.

This machine allowed cartographers to plot the contours

and elevations of mountainous areas using aerial photos to create maps

far quicker than even the speediest draughtsman.

Stereo plotting has made mountains into molehills

as far as the hard grind of map-making is concerned.

Here's how they get those squiggles

which show you the height of mountains.

Draughtsmen trace the lines the stereo plotter's made

on wax-coated glass, a process known as "scribing a mould".

Climbing these hills would be much less work

than drawing them so accurately.

Although scribing mould was a step forward from hand drawing maps,

this process still demanded a lot of time

and effort from the draughtsperson.

We used basic tools, but they would have different cutters in them

at different widths.

Tools that we use, this one for drawing straight lines with.

It scribes the line on the plastic.

And there's a tripod for doing curvy lines.

You move down and scratch the coating off,

using that to move it round.

Those were the two basic tools.

And what we call a dot cutter.

So basically we line it up and we need the dot.

And just drill a hole.

Hopefully not right through it.

To do an Outdoor Leisure map, one side of an Outdoor Leisure map

took two years.

Despite the incredible attention to detail

of the Ordnance Survey's cartographers, historically,

some areas of the country have always been off limits.

Most famously, I guess, with Ordnance Survey, was from the '20s

right the way through until very recently, they had a policy

of keeping off the map - this was government policy -

keeping off the map sites of military sensitivity.

During the Cold War, Britain's security was thought

to be under grave threat from the Soviet Union...

..and nearly 5,000 sensitive areas were excluded from OS maps.

There were some really crazy ones. When I was a kid in the '70s

we used to go and stay in Scarborough every year,

up in North Yorkshire. And a favourite day trip was to go out

and look at the golf balls on the North Yorkshire Moors

of the Fylingdales early warning system. You could get

a coach trip there, you could buy postcards of the place.

But there was just a blank, nothing on the Ordnance Survey map.

I mean, who did they think they were kidding?

Certainly not the Russians, anyway.

After the fall of the Iron Curtain in the late 1980s,

some surprisingly detailed Soviet maps of 92 British towns and cities

came to light.

Ironically, they featured in glorious detail

all the military sites which the OS had been forced to omit...

..and much more on top.

And it's things that we don't normally see on maps.

It's things like the speed of flow of rivers

and whether a river is tidal or not.

It's things like the width of roads

and the clearance of the carriageways

and how many carriageways and what the surface of a road is made of.

It's things like the depth to which a channel has been

dredged for clearance.

They've collected as much information as they could possibly find

and put it on a map.

These maps are still top-secret in Russia.

It is assumed they were completed using a mixture of existing maps

of the UK, spies on the ground and photography from above.

If you're going to invade, they are very much useful

if somehow this is now your territory.

Then there is what you need

to rule the place, or to run the place.

Clearly they were most interested in objects of military importance,

and a particularly good example is the Chatham Dockyard in Kent,

where British submarines were being built

throughout the Cold War period.

And on the Ordnance Survey maps, that whole area is shown as

an empty blank space.

Whereas what we have here is the Soviet map from 1985.

We can see each of the military buildings identified

and also the individual railway lines,

the docks and the dry docks.

And what's interesting, of course, is the contemporary Ordnance map

has none of that information.

In fact, attention was drawn to it

by the fact it was a blank space.

It was easier to find secret sites by looking for the blank spaces

on the Ordnance maps!

The Soviet cartographers who mapped the UK's major cities

during the '60s and '70s would have been helped greatly

by the use of satellite imagery.

Technology at this time was developing rapidly

and the Ordnance Survey were early adopters of the computer.

I remember the staff being...

Certain staff members were thought to have an aptitude

for computer logistics.

..being tested.

And there was a very primitive computer brought in,

and our fastest draughtsman was ranged against

this computer to see who was going to finish the map first.

And obviously, not a huge map,

but a number of key skills and tricks, what have you.

And I think it more or less came out 50/50, you know.

But man didn't stay level with machine for very long.

By the early 1970s, a revolutionary shift towards

digital map-making was underway.

The OS's huge archive of topographical data

was digitised onto spools of magnetic tape.

These computers were much more efficient than humans.

This unit is capable of plotting a map at up to 40 inches a second.

A skilled draughtsman might take days to do a sheet like this.

This machine will finish it off in minutes.

The first computer-generated map came just two years before

another big shift for the Survey -

moving from the imperial to the metric era.

The old one-inch map was replaced by the 1:50,000 scale.

These maps became known as the Landranger series.

For hardcore OS fans, they quickly gained iconic status.

The northern part of the country came out in 1976.

And at nine o'clock in the morning on the day they came out,

I was through the doors of WH Smith's in Kidderminster,

and there they were! It was kind of, I guess, the Harry Potter launch

of its day as far as I was concerned. But I was the only one

in the queue, as you can probably imagine.

During the '70s, the Ordnance Survey was encouraged by the government

to become a little more... Well, relaxed.

In 1974, it announced that the director-general

no longer needed to have a military background.

Yet again, the Ordnance Survey was adapting to meet

the demands of a new Britain.

Surveying methods had changed beyond all recognition.

Infrared beams were now used to measure distances.

But sometimes, nature had other ideas.

OS 12 to OS 13, will you move to the corner of the barn, please?

'I think you'll have to shoo the cattle out of the way, over.'

OK, Rog, wilco.

CATTLE MOO

The OS digitised the last of its 230,000 different maps

in 1995, making Britain the first country in the world

to complete a programme of large-scale electronic mapping.

It saw that its future lay squarely in this direction.

In 2001, a new computer system was introduced -

the OS MasterMap.

It's now the biggest geographical database in the entire world,

containing over 440 million man-made and natural landscape features

of the British Isles.

This huge geographical archive is a valuable commodity

for the OS and it absorbs new data at a phenomenal rate,

with up to 10,000 changes being made to it in a day.

One of the ways the MasterMap reacts to the smallest

change in the physical fabric of the nation

is through its all-seeing digital eye in the sky.

My job is, basically, to cover 80,000 kilometres per year

of Great Britain...

..and hopefully accumulate 50,000 photos in that time.

CAMERA SHUTTER CLICKS

This camera here is a 196-megapixel camera,

so it's a pretty decent resolution there,

much better than what you've got on your iPhone 5.

We've got eight lenses underneath this camera here.

There's four colour.

Er, three panchromatic, so black and white,

and one infrared.

So we're getting a lot of data - they're all taking images

at the same time.

Once we go over the specific site, it automatically takes the images.

And then we can view them on this screen here, which allows us

to quality control them.

Being up in the sky for eight hours at a time, you get to see

a lot of land, you get to see some great features.

You also get to see some great infrastructure as well.

The freedom up here, really, it's brilliant.

These aerial photographs are compared against

the existing OS map.

Any changes are updated immediately on the MasterMap.

Over 90% of the Ordnance Survey's revenue stream

is now made up from selling its digital data.

But the OS are not the only people watching

and profiting from our every move.

In recent years, Google has been mapping its way around the world,

creating an instant-access, interactive picture of the planet.

I think the problems that the Ordnance Survey faces are twofold.

One is that you are in an age of globalisation,

so the concept of mapping the nation state is,

it seems to me, in a long period of decline.

The other problem, of course, is the decline of

the paper map.

Online, digital geospatial applications are now predominating,

so the OS is in a real problem.

It's now become absolutely ubiquitous to use online maps.

Most of us now access maps through sat navs or our phones.

And sales of those old favourites, the Landranger and Explorer maps,

have been gradually declining.

But there are no plans to abandon the traditional paper maps.

The experience of reading a physical map, making sense of its

funny-shaped symbols and contours are part of its pleasure,

and its sheer physical scale is hard to beat.

Big paper maps give you an idea of where you sit in a bigger landscape.

If you've got a narrow GPS map on your screen as you're driving,

all you see is a narrow strip of information.

If you've got an Ordnance Survey map, you see all of

the contextual material as well. You see exactly where you are sitting

in the landscape.

You can very clearly see, because the symbols differentiate

between a, you know, a coniferous wood and a deciduous wood.

And you can tell the difference between a wide river

and a narrow stream.

Despite the bigger picture Ordnance Survey offers,

digital maps have taken over our view of the world.

So much so, that some have warned we are losing the ancient art

of reading a map.

One group who has always placed value in the power

of map-reading is the Scouts.

As an organisation, they have always been one of the OS's biggest fans.

But can today's tech-savvy Scouts be convinced that traditional

map-reading skills and OS maps are still relevant?

I remember learning how to use Ordnance Survey maps myself

when I was in the Scouts,

and that's not a knowledge that ever goes away.

You learned because it was a skill you didn't learn anywhere else.

And, you know, six-figure references, compass work, maps,

was something new, it was something interesting,

something exciting. You remembered to know that if you looked

at an Ordnance Survey map, a red triangle meant you were near

a Youth Hostel.

For this group of teenagers, whose first instinct

to find a youth hostel would be a Google search,

they're learning traditional navigational skills.

So, if we are there, I would like you to figure out how long

it will take us to get to this point here.

Well, we also to use the compass to measure

how many contour lines there are, which determines the steepness

of the hills that we're going up.

So, there's one, two,

three, four, five and that determines the...

It's not quite clear how much the joy of old-school navigation techniques

beats more modern technology for these boys.

So, it should take us 20 minutes.

But one benefit is clear...

You don't require a signal for a map, whereas you do for a phone.

Plus phones run out of battery, so it doesn't really help if you're

out in the forest and you're...

Going to get stuck, aren't you?

Though, as we all know, the hardest thing about using an OS map

is folding it up.

We'll do creases in the middle. This is, like, the main one.

Sort of fold that in half, and then it sort of...

folds in on itself, doesn't it?

You have get it precise, get the creases in the right position,

match them together. It takes a lot.

Sometimes I've to get one of the leaders to do it!

-Are you Succeeding?

-A little.

-Yeah, we're getting there.

-Fold it back.

-Fold it back?

And then it just folds. I mean, that looks simple, but...

-It's not that...

-..it's not when you're on your own and...

It's taken a lot of practice.

Over the past 226 years, the Ordnance Survey has followed

every move our nation has made.

It's mapped the geography of our lives and helped us win wars.

And it's done so with a world-beating use

of new technology...

..and a rather eccentric spirit of adventure.

The Ordnance Survey is absolutely a Great British success story,

and it forms a model for many national mapping agencies

around the world.

Certainly, the Ordnance Survey makes Britain pretty much

the leading country in the world in terms of possessing

accurate geographical information about itself.

It's the greatest cartographic institution in the world

and it could not be more British.

Well, in some ways, the Ordnance Survey is

a perfect mirror of Britain,

at its best and at its worst.

I mean, at its best - you know, entrepreneurial

and go-getting and quietly ambitious for the country.

A beautiful fusion of art and science.

And then, it is as an organisation, and always has been,

rather stuffy, rather pompous, rather self-important.

Britain in a nutshell.

The gridlines and coordinates of the OS map have always been

a trusty travelling companion.

I cannot possibly imagine this country functioning without

Ordnance Survey maps.

Perhaps the greatest testament to the Ordnance Survey

is that for many of us, they don't just produce maps,

the OS ARE maps.

And the simple charm of their paper map can never be replaced.

Brian gets quite irate when people say,

"You don't need to tell us where you live, because we've got sat nav."

So Bryan says, "No, you should be using an Ordnance Survey map."

You can't beat an OS paper map.

The OS map will always be the best.