Inhabitance of the site of Tripoli goes back to at least the 14th century BC, but it was not until the 9th century BC that the Phoenicians established a small trading station there. Under the successors of Alexander the Great during the Hellenistic period, Tripoli was used as a naval shipyard. Under Byzantine rule, along with other coastal cities, Tripoli was destroyed by an earthquake and tidal wave in 551. In the 12th century, Crusaders entered Tripoli causing extensive destruction. The city then fell into Mamluk Sultan Qalawun who destroyed the old port city to build a new one in addition to numerous religious secular buildings. During the Turkish Ottoman rule, Tripoli retained its prosperity. Excavations revealed part of the ancient southern port quay and a necropolis from the end of the Hellenistic period.