Susah (sōō´sä) or Sousse (sōōs), ancient Hadrumetum, city (1994 pop. 125,000), NE Tunisia, on the Gulf of Hammamat, an arm of the Mediterranean Sea. It is a fishing port and export point for olive oil. The city was founded c.9th cent. BC by the Phoenicians. It was destroyed (AD 434) by the Vandals and rebuilt by Justinian. Susah was briefly held by Roger II of Sicily (c.1150). Ancient remains include Christian catacombs.