The team, directed by Professor Stuart Campbell and Dr Jane Moon, both from Manchester, and independent archaeologist Robert Killick, first spotted the amazing structure – thought to be an administrative complex serving one of the world's earliest cities– on satellite.

It was after carrying out geophysical survey and trial excavations at the site of Tell Khaiber that they were able to confirm the size of the complex at about 80 metres square – roughly the size of a football pitch.
"We provisionally date the site to around 2,000 BC, the time of the sack of the city and the fall of the last Sumerian royal dynasty. "

The team aim to analyse plant and animal remains found at the site to help reconstruct environmental and economic conditions in the region 4,000 years ago. Marshy conditions are thought to have prevailed, with the head of the Gulf being much further north, so that maritime trading was possible to obtain vital natural resources from India and the Arabian peninsula.