Isthmus

An isthmus (pronunciation: /ˈɪsθməs/ or /ˈɪsməs/; plural: isthmuses; from Ancient Greek: ἰσθμός isthmos "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.

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