Strait of Gibraltar

The Strait of Gibraltar is the stretch of water that separates Europe from Africa and joins the Mediterranean Sea to the Atlantic Ocean. It has been strategically and economically important since vessels began venturing into the Atlantic towards the end of the second millennium B.C. The Romans called it the “Pillars of Hercules,” (in Latin, Fretum Herculeum or Fretum Gaditanum.) It was traditionally thought of as the western boundary of the ancient Greek and Roman worlds. Strictly speaking, Cadiz (Gades), a port on Spain's Atlantic coast, is further west. Cadiz was founded by the Phoenicians about 1100 BC.

It is approximately 58 km. (36 miles) long. Its northern (European ) coast stretches from Spanish Cape Trafalgar in the west to Europa Point at the eastern side of the Bay of Trafalgar in the east. Its southern coastline stretches from Cape Spartel in Morocco in the west to Punta Almina in the Spanish African enclave of Ceuta in the east. Between Capes Trafalgar and Spartel it is 43 km (27 miles) wide – at the Rock of Gibraltar and Mount Hacho in Ceuta) it is 23 km (14 miles) wide. It is 13 km (7.75 miles) wide at its narrowest point.

The Strait has an average depth of 365 metres (1200 ft) with its shallowest point being 50 metres (164 ft.) There is a general flow of water from west to east because the Mediterranean loses more water from evaporation than its rivers can replace and needs replenishment from the Atlantic. (An interesting fact when one considers that mighty rivers like the Nile, the Danube, the Don, the Volga and others all add to it.) The surface current runs from over two knots to as much as six knots and this was a problem during the days of sail and oared propulsion. Well below the surface there is an opposite current, colder and quite saline, running into the Atlantic.

The name, Gibraltar, derives from that of the Berber Muslim general, Tariq ibn-Ziyad, who crossed the Strait and invaded southern Spain in AD 711. After defeating the Goths in battle, he began fortifying what is now the Rock of Gibraltar – Jebel Tariq. This fortress, completed in 743 was the first of an increasingly powerful series of fortifications that would continue into the present era.

The Christians took Gibraltar in 1309 and a Christian settlement was established there. Control of the northern shore of the Strait was then contested bitterly for much of the 14th century between, not only Christian and Islamic forces, but various Christian kingdoms in the Iberian Peninsula. Meanwhile, in the last decade of the 14th century, Ceuta, on the southern shore, was invaded and taken over in a “crusade” by a prince of Portugal, later to be known as Henry the Navigator. By the first decade of the 1400s, parts of both shores were in Christian hands. Today, Ceuta is a part of Spain, an “Autonomous City” of that country.

Reference

• Hattendorf, John B, (editor in chief) The Oxford Encyclopedia of Maritime History Oxford University Press (2007) Volume 2. pp. 87-91.