Simplified diagram

A strait is a narrow channel of water that connects two larger bodies of water, and thus lies between two land masses. The terms strait, channel, and passage can be synonymous and interchangeable, although channel has other meanings. Many straits are economically important. Straits can lie on important shipping routes , and wars have been fought for control of these straits. Numerous artificial channels, called canals, have been constructed to connect two bodies of water over land.

Well-known straits in the world include the English Channel, between England and France, which connects the North Sea with the Atlantic Ocean off France; the Strait of Gibraltar, which is the only natural passage between the Atlantic Ocean and the Mediterranean Sea; the Bosporus and the Dardanelles, which connects the Mediterranean and the Black Sea; and the Straits of Malacca, which lie between Malaysia and Sumatra and connect the Indian Ocean with the South China Sea.

Although rivers and canals often form a bridge between two large lakes or a lake and a sea, and these seem to suit the formal definition of straits, they are not usually referred to as straits. Straits are typically much larger, wider structures that do not have water running in a single direction, and normally connect two seas.

Straits are the duals of isthmuses. That is, while straits lie between two land masses and connects two larger bodies of water, isthmuses lie between two bodies of water and connect two larger land masses.

See also

• List of straits