Mesopotamia, literally meaning "between rivers", was the land between the Tigris and the Euphrates in the Middle East. It was the site of the first known cities, and the civilisations of Sumer and Babylon were founded here.

They developed written language, arithmetic and a calendar, and kept excellent records of astronomical events over long periods of time.

It is tempting to speculate how the science of astronomy might have advanced if the later Greeks had combined their philosophical flair with the Mesopotamians' observational skills.