The Bab-el-Mandeb (Arabic for "the gate of tears") is the strait separating the continents of Asia (Yemen on the Arabian Peninsula) and Africa (Djibouti, north of Somalia on the Horn of Africa), connecting the Red Sea to the Indian Ocean (Gulf of Aden).

It derives its name from the dangers attending its navigation, or, according to an Arab legend, from the numbers who were drowned by the earthquake which separated Asia and Africa. It is both strategically important and one of the world's busiest shipping lanes.

The distance across is about 20 miles (30 km) from Ras Menheli on the Arabian coast to Ras Siyan on the African. The island of Perim , divides the strait into two channels, of which the eastern, known as the Bab Iskender (Alexander's Strait), is 2 miles (3 km) wide and 16 fathoms (30 m) deep, while the western, or Dact-el-Mayun , has a width of about 16 miles (25 km) and a depth of 170 fathoms (310 m). Near the African coast lies a group of smaller islands known as the "Seven Brothers." There is a surface current inwards in the eastern channel, but a strong under-current outwards in the western channel.