What is the oldest known map of the world, and what did it show?

The oldest known map of the world is a Babylonian clay tablet, written in Akkadian and dated to no earlier than the 9th century BC, with the late 8th or 7th century BC more likely. It is schematic, more a diagram than a chart, but the text on it describes the oldest known depiction of the world as people then knew it.

The picture is simple. The Euphrates runs down the middle from top to bottom, ending in a marsh. Babylon sits on the river, north of centre. Around this Mesopotamian heartland runs a ring of water, the 'bitter river' or Ocean. Beyond that ring, seven or eight triangles stick out like points of a star: far-off regions, perhaps imagined as mountains. It is no survey: Habban, the capital of the Kassites, is even drawn in the wrong place.

The writing around the map hints at what it was for. The text above it seems to describe the god Marduk parting the primeval salt Ocean to create land and sea, and pictures the land as a kind of giant raft floating on that sea. On the back, each distant region is introduced by a phrase about travelling 7 leagues to reach it. One region may be a desert so barren that even birds cannot cross it. Another may hold the resting place of the ark of the flood hero, perhaps the same mountain as the Biblical Mount Ararat.

The tablet was dug up by Hormuzd Rassam at Sippar, 60 km north of Babylon, and reached the British Museum in 1882, with its text first translated in 1889. Its last lines apparently name the scribe who wrote it. Scholars have argued about how to read it ever since it was found.