Lagoon

Balos coastal lagoon of northwestern Crete. The shallow lagoon is separated from the Mediterranean Sea by narrow shoals connecting to a small, rocky mountain.
Garabogazköl lagoon in Turkmenistan
Venetian Lagoon

A lagoon is a shallow body of water separated from a larger body of water by a narrow landform, such as reefs, barrier islands, barrier peninsulas, or isthmuses. Lagoons are commonly divided into coastal lagoons (or barrier lagoons) and atoll lagoons. They have also been identified as occurring on mixed-sand and gravel coastlines. There is an overlap between bodies of water classified as coastal lagoons and bodies of water classified as estuaries. Lagoons are common coastal features around many parts of the world.