When I think about maps I think about human settlements shifting over a static landscape. But the landscape is not static. Within memory of our species, at about the same time the world’s first cities began to appear in the Middle East, the coastline of northern Europe was radically different. As late as 5,000 B.C. the depressed sea levels of a waning ice age left an island about the size of the Netherlands exposed in the North Sea. It is named Doggerland after the sea-mount called Dogger Bank that still exists below the waves.
Moving backward in time to the Early Holocene we find the island firmly attached to the continent as a low ridge called the Dogger Hills. Even earlier, at the height of the Devensian ice age, the Entire North Sea is a marshy plain draining into a channel between Scotland and Norway.