Maps come in all shapes, sizes and mediums, and this one, made by an unknown Chinese mapmaker dated 1130, is carved onto a meter-high stone, or stele, showing China’s coastline (including Hainan Island) and network of rivers (especially the Yellow and Yangtze) with remarkable accuracy. It is called the ‘Yu ji tu’, or ‘Map of the Tracks of Yu’, and was made under the Song dynasty (907-1276). For Joseph Needham, the great historian of Chinese science, it revealed ‘the extent to which Chinese geography was at that time ahead of the West’. It is the first Chinese map to use a grid with each of its 5,000 squares representing one Chinese li (approximately 50 kilometres) giving a scale of around 1:4,500,000. The title refers to the ancient legendary text the ‘Yu Gong,’ which describes an archaic, unified China defined by rivers and mountains. It is therefore a map about a legendary, lost China, which also doubles up as a printing press: the stele has been used to take rubbings of what is carved on its surface, three-hundred years before print reached Europe.