Apart from the book and its cover, I took inspiration from Ordnance Survey maps (not meaning copying). I've been a huge fan of these maps: they are one of those managing to be insanely precise and visually precious at the same time.
I have an impression that official cartographic materials match their countries’ stereotypes: Swiss maps are dramatically beautiful and precise; old Soviet maps are brutal, lacking decorations, precise yet shifted - they kinda try to trick you all the time. In the same way, OS maps represent Britain: smooth-coloured, cosy, packed with things and quirks (check out
Ordnance Survey puzzles!), with beautiful icons and great typography. And - it might be a common knowledge, but I wasn’t aware of that before doing a small research for this backstory, and it dilutes my naively unsullied image - they appeared as a means to control Scotland (which was also very British):
Interestingly enough its roots began in 1747 when Lieutenant-Colonel David Watson proposed to King George II a survey of the Highlands, as a means of controlling the Scottish clans after the Jacobite rising in 1745.vintagehikingdepot.com(Sorry, I'll just leave it here.)
Meanwhile, in the previous Bryson’s book about England, he mentions Ordnance Survey maps:
As a rule, I am not terribly comfortable with any map that doesn’t have a You-Are-Here arrow on it somewhere, but the Ordnance Survey maps are in a league of their own. Coming from a country where mapmakers tend to exclude any landscape feature smaller than, say, Pikes Peak, I am constantly impressed by the richness of detail on the OS 1:25,000 series. They include every wrinkle and divot of the landscape, every barn, milestone, wind pump and tumulus. They distinguish between sand pits and gravel pits and between power lines strung from pylons and power lines strung from poles. This one even included the stone seat on which I sat now. It astounds me to be able to look at a map and know to the square metre where my buttocks are deployed.Bryson in 'Notes from a Small Island'