Heracleion: Submerged City of Ancient Egypt

Heracleion, was an ancient Egyptian city near Alexandria whose ruins are located in Abu Qir Bay, currently 6.5 km off the coast. Its legendary beginnings go back to as early as the 12th century BC, but until recently the city had been known only from a few literary and epigraphic sources including the writings of such ancient Greek historians as Diodorus and Strabo, as well as Herodotus.

Heracleion reportedly grew in importance from the 6th to the 4th century BC, as revealed by numerous archaeological finds... during the waning days of the Pharaohs... when it became Egypt's main port. The city was originally built on some adjoining islands in the Nile delta, and was intersected by canals.

It was believed that Paris and Helen of Troy were stranded there on their flight from the jealous Menelaus, before the Trojan war began, and was further suggested that Heracles, himself, had visited the city, and that Heracleion had gained its name from him. The city had a large temple of Khonsou, son of Amun, who was known to the Greeks as Heracles. Pharaoh Nectanebo I made many additions to the temple in the 4th century B.C.

The city sank in the 6th or 7th century A.D., probably due to major earthquakes and floods. The ruins submerged in the sea were finally located and rediscovered by the French underwater archaeologist Franck Goddio in 2000.