Enki lives in the Abzu. At one point, he feels that he should have a palace temple (city) for himself. He builds Eridu in the depths of the Abzu. It floats to the surface and he attaches it to the shore. Then he begins to worry because he hasn't gotten An's permission and blessing. He travels to An's city, Uruk ("Erech"). He has a great feast with much wine and beer. Enki asks An if he might build a city and if An would bless it. An grants permission and gives Enki the Seven Tablets of Law or Civilization as a blessing. Enki takes them back to his city, making his city the most important city in Mesopotamia.
Later, Inanna, who shares Uruk with An, decides that she should have the greatest city and resolves to wrest the power away from Enki. She takes her prime minister Ninshubur and they sail down the Euphrates. When they arrive at Eridu, they surprise Enki. He asks them why they've come. Inanna expresses concern for him. Enki, foolishly, is flattered. He lays out a great feast in her honor. Enki drinks a lot and then says that if there is anything he can do for Inanna, she need only ask. Inanna asks to "borrow" the Seven Tablets, to which Enki agrees. She and Ninshubur take them and leave immediately. As Enki sobers, he realizes he has been duped and sends Isimud after Inanna in another boat. He catches them and asks for the tablets back. They refuse. He conjures up monsters, but the two are oblivious. They arrive in Uruk and keep the tablets.
Eridu and Uruk are real cities of the ancient world < 3,000 B.C. Eridu was the greatest. Power shifted to Uruk at some point. These stories are a political allegory to explain this transfer of power.