The man who has mapped Scotland - millimetre by millimetre - for 40 years

Over great landscapes and in all weathers, he has cycled and trodden deep terrain to keep Ordnance Survey maps as complete and accurate as possible. He is, as he sees it, the eyes on the ground as Scotland’s landscapes change and evolve.

As towns, cities and countryside alter and new buildings and structures emerge, from the V&A in Dundee to the new deep water port in Stornoway, he adds the new detail quickly and with pinpoint accuracy.

“You get this sort of unofficial ownership over your area. Every surveyor has a great pride in their work. Everything is getting bigger - roads, houses, schools. You are working hard every day to make sure they are mapped as soon as possible. People need to know what is there," Mr Dunbar said.

Mr Dunbar started with OS aged 19 and jobs that would have taken days to complete can now be finished in minutes as trig points, square sets and optical prisms give way to GPS, satellite clusters and drones.

In Dunfermline on Wednesday morning, Mr Dunbar receives information about his location - to the millimetre - from satellite constellations sitting high in low earth orbit as he works on a ground survey of a new housing scheme.

This level of accuracy comes with the help of OS Net, the firm's network of 100 fixed satellite bases, with around a third in Scotland, from Butt of Lewis to Dumfries and Galloway. 

Mr Dunbar walks with his handheld GS15 receiver, tapping the ground to follow the lines of the development. Every recess, twist and turn and back garden is mapped as he moves. Doorbells are rung, access is granted.

Information that has travelled hundreds of kilometres to Dunfermline reaches him in seconds. Every day, there are more than 20,000 updates to the OS database as new features are added.

While out on a job, people often ask Mr Dubar why Amazon delivery drivers can’t find their new house. Now they can, he tells them.

Blue light services and utilities companies also rely on the information OS provides, as does Registers of Scotland to ensure the boundaries of property across the land.

Mr Dunbar, who lives in Ardrossan, is one of 22 surveyors in Scotland and is chiefly responsible for mapping Ayrshire, Inverclyde and some of the islands, including Mull, Islay and Tiree. Over time, he has seen great changes in the landscape - and the techniques used to measure them. The graphic survey work of old is becoming a “lost art”.

He said: “The first time I went to Tiree was probably in the 1990s when we still had sketching cases. So I arrived with my bike and nothing to plug in, just a sharp pencil, a set square, a tape measure, a plastic map and an optical prism.”

The last time he was on Tiree was earlier this month on holiday with his family.

“We stayed on a new campsite which wasn’t even on the map yet. I don’t know how we found it,” he added.

Soon he will return to map the campsite, not with a sharpened pencil, but most likely with a drone.

Mr Dunbar was one of the first OS surveyors to be trained in drone technology. At roughly 11.30am on Wednesday morning, a brand new superschool in Dunfermline, which is due to open after the summer holidays, did not feature in the OS database. After a drone flyover that took roughly 10 minutes, a 3D model of the school was produced from around 300 images. From here, topographical information will appear on the map in a matter of days.

The drone is so powerful that it picks up the shape of his sandwich lying on the grass.

Mr Dunbar’s work refines information gathered by OS planes, which last year covered around 48,000 square kilometres of Scotland. Soon, he will visit a cottage picked up on Ulva, whose name he needs to double check - “I prefer to see it written down on a wall or door with my own eyes “ and match it to the location and address.

The work will inform revisions of the OS print maps and information included in its app, which now raises more revenue for the firm than the printed product.

Mr Dunbar’s love of maps started as a young boy in the Scouts and was developed in the hills. A key moment was seeing Castle Semple featured on a William Roy map produced by the legendary military surveyor from the 1770s. Mr Dunbar described him as a “hero”.

“This map  was a beautiful work of art. I was fair taken with it,” he said.

Asked what he finds so powerful in a map, he added: “It is everything about it, from the colours to the contours to the Gaelic words, to it coming to life with the text and the shapes of islands. It is like a bird’s eye view - a miniature of the land it is representing.”

Ordnance Survey has its roots in William Roy’s survey work - with the organisation “intrinsically linked” to the Scottish landscape, it said.

The Roy Military Survey followed the Jacobite Rising of 1745 when the Hanoverian military commanders in Scotland found themselves’ greatly embarrassed for want of a proper Survey of the Country,' ' according to accounts.

What started out as a military sketch of the Highlands in 1745 became a map of the whole country. Roy, originally from Carluke, used only simple compasses, 50ft chains and the naked eye. It took him eight years.

More than 200 years later, a map may be more rapidly produced. But like Mr Roy, the ingenuity and attention to detail and skill of today’s map makers is not hard to find.