Eridu is traditionally considered the earliest city in southern Mesopotamia based on the Sumerian King List.

Located 24 kilometers south-southwest of the ancient site of Ur, Eridu was the southernmost of a conglomeration of Sumerian cities that grew around temples, almost in sight of one another.

His temple was called E-Abzu, as Enki was believed to live in Abzu, an aquifer from which all life was thought to stem.

[5] Eridu is located on a natural hill in a basin approximately 15 miles long and 20 feet deep, which is separated from the Euphrates by a sandstone ridge called the Hazem.

Excavation there resumed from 1946 to 1949 under Fuad Safar and Seton Lloyd of the Iraqi Directorate General of Antiquities and Heritage.

Among the finds were a Ubaid period terracotta boat model, complete with a socket amidship for a mast and hole for stays and rudder, bevel-rimmed bowls, and a "lizard type" figurine like those found in a sounding under the Royal Cemetery of Ur.

Soundings in the cemetery showed it to have about 1000 graves, all from the end of the Ubaid period (Temple levels VI and VII).

[24] These archaeological investigations showed that, according to A. Leo Oppenheim, "eventually the entire south lapsed into stagnation, abandoning the political initiative to the rulers of the northern cities", probably as a result of increasing salinity produced by continuous irrigation, and the city was abandoned in 600 BC.

[25] In 1990 the site was visited by A. M. T. Moore who found two areas of surface pottery kilns not noted by the earlier excavators.

[26] In October 2014 Franco D’Agostino visited the site in preparation for the coming resumption of excavation, noting a number of inscribed Amar-Sin brick fragments on the surface.

[31] In March 2006, Giovanni Pettinato and S. Chiod from Rome's La Sapienza University claimed to have discovered 500 Early Dynastic historical and literary cuneiform tablets on the surface at Eridu "disturbed by an explosion".

The dig-house had been built using bricks from the demolished Leonard Woolley’s expedition house at Ur (clearly spelled out in the 1981 Iraqi excavation report to avoid confusion to future archaeologists.

[9] The urban nucleus of Eridu was Enki's temple, called House of the Aquifer (Cuneiform: 𒂍𒍪𒀊, E₂.ZU.AB; Sumerian: e₂-abzu; Akkadian: bītu apsû), which in later history was called House of the Waters (Cuneiform: 𒂍𒇉, E₂.LAGAB×HAL; Sumerian: e₂-engur; Akkadian: bītu engurru).

Aside from Enmerkar of Uruk (as mentioned in the Aratta epics), several later historical Sumerian kings are said in inscriptions found here to have worked on or renewed the e-abzu temple, including Elili of Ur; Ur-Nammu, Shulgi and Amar-Sin of Ur-III, and Nur-Adad of Larsa.

Excavation has shown that the city was founded on a virgin sand dune site with no previous habitation.

At a small mound 1 kilometer north of Eridu two Early Dynastic III palaces were found, with an enclosure wall.

Twelve neolithic clay tokens, the precursor to Proto-cuneiform, were found in the Ubaid levels of the site.

Uruk finds included decorative terracotta cones topped with copper, copper nails topped with gold, a pair of basalt stone lion statues, columns several meters in diameter coated with cones and gypsum, and extensive Uruk period pottery.

"[49] Three Third Dynasty rulers designated Year Names based on the appointment of an en(tu)-priestess (high priestess) of the temple of Enki in Eridu, the highest religious office in the land at that time.

After the fall of Ur III the site was occupied and active during the Isin-Larsa period (early 2nd Millennium BC) as evidenced by a Year Name of Nur-Adad, ruler of Larsa "Year the temple of Enki in Eridu was built" and prior texts of Isin rulers Ishbi-Erra and Ishme-Dagan showing control over Eridu.

[51] This continued in the Old Babylonian period with Hammurabi stating in his 33rd Year Name "Year Hammu-rabi the king dug the canal (called) 'Hammu-rabi is abundance to the people', the beloved of An and Enlil, established the everlasting waters of plentifulness for Nippur, Eridu, Ur, Larsa, Uruk and Isin, restored Sumer and Akkad which had been scattered, overthrew in battle the army of Mari and Malgium and caused Mari and its territory and the various cities of Subartu to dwell under his authority in friendship" In an inscription of Kurigalzu I (c. 1375 BC), a ruler of the Kassite dynasty one of his epitaphs is "[he one who ke]eps the sanctuary in Eridu in order".

[53] The Neo-Assyrian emperor Sargon II (722–705 BCE) awarded andurāru-status (described as "a periodic reinstatement of goods and persons, alienated because of want, to their original status") to Eridu.

[54] The Neo-Babylonian ruler Nebuchadnezzar II (605–562 BC) built at Eridu as evidenced by inscribed bricks found there.

[55] In some, but not all, versions of the Sumerian King List, Eridu is the first of five cities where kingship was received before a flood came over the land.

[nam]-lugal an-ta èd-dè-a-ba [eri]duki nam-lugal-la eridugki a₂-lu-lim lugal mu 28800 i₃-ak a₂-lal₃-ĝar mu 36000 i₃-ak When kingship from heaven was lowered, the kingship was in Eridu In Eridug, Alulim became king; he ruled for 28800 years.

[60] In the flood myth tablet[61] found in Ur, how Eridu and Alulim were chosen by gods as first city and first priest-king is described in more detail.

At first Enki, the god of Eridu, attempted to retrieve these sources of his power but later willingly accepted that Uruk now was the centre of the land.