The Gough Map is a new book that details the fascinating history of the oldest accurate map of Britain, which is amazingly accurate (except for the Scotland bits), especially considering that it was made around 1360. It's also extremely lovely:



"There are 600-odd places and, if you compare it with a modern map, most of them are in pretty much the right spot," says Millea.

"We don't know whether they did the coastline first then filled in the interior, or whether it was done by word of mouth – a verbal map – so they put in London then worked outwards, adding places they knew."

Nick Crane, topographer and presenter of TV series Map Man, thinks they may have used an astrolabe – a highly technical instrument used by classical astronomers, navigators and astrologers which involved checking the horizon, the stars, the sun and all sorts of angles.

"This could be the beginning of mathematical map-making – some of the points of latitude have probably been measured through astronomy," he says.