The Oldest Known Map: The Map of Nippur
This ancient clay tablet dates to the 14th-13th century BC. It shows a map of the countryside around the Mesopotamian city of Nippur, located in the middle of the southern Mesopotamia floodplain, near the modern city of Diwaniyah, Iraq. The inscription on the tablet is in cuneiform.
The University of Pennsylvania was excavating in Nippur from 1889 until 1900 and during that time they discovered thousands of clay tablets. This map may have been discovered at that time, but its importance was not recognized until quite some time later.