Isthmus

For other uses, see Isthmus (disambiguation).

The sandy isthmus or tombolo connecting North and South Bruny Island in Tasmania, Australia

An isthmus ( /ˈɪsθməs/ or /ˈɪsməs/; plural: isthmuses; from Ancient Greek: ἰσθμός, romanized: isthmos, lit. 'neck') is a narrow piece of land connecting two larger areas across an expanse of water that otherwise separates them. A tombolo is an isthmus that consists of a spit or bar, and a strait is the sea counterpart of an isthmus.

Canals are often built across isthmuses, where they may be a particularly advantageous short cut for marine transport. For example, the Panama Canal crosses the Isthmus of Panama, connecting the North Atlantic and Pacific Oceans; the Suez Canal connects the Mediterranean Sea and the Indian Ocean, cutting across the western side of the Isthmus of Suez, formed by the Sinai Peninsula; and the Crinan Canal crosses the isthmus between Loch Crinan and Loch Gilp, which connects the Kintyre peninsula with the rest of Scotland.

See also

• Land bridge
• List of isthmuses
• List of straits