Mediterranean Sea million years ago (mya) in less than two years by the Zanclean flood. Water poured in from the Atlantic Ocean through a newly breached gateway now called the Strait of Gibraltar at an estimated rate of about three orders of magnitude (one thousand times) larger than the current flow of the Amazon River. The Mediterranean Sea has an average depth of and the deepest recorded point is in the Calypso Deep in the Ionian Sea. The coastline extends for . A shallow submarine ridge (the Strait of Sicily) between the island of Sicily and the coast of Tunisia divides the
Mediterranean Sea when Augustus founded the Roman Empire, the Romans referred to the Mediterranean as "Mare Nostrum" ("Our Sea"). For the next 400 years, the Roman Empire completely controlled the Mediterranean Sea and virtually all its coastal regions from Gibraltar to the Levant. Darius I of Persia, who conquered Ancient Egypt, built a canal linking the Mediterranean to the Red Sea. Darius's canal was wide enough for two triremes to pass each other with oars extended, and required four days to traverse. The Western Roman Empire collapsed around AD 476. Temporarily the east was again dominant as Roman power lived on in