Tidal island

Island accessible by foot at low tide

A tidal island is a raised area of land within a body of water, which is connected to the larger mainland by a natural isthmus or man-made causeway that is exposed at low tide and submerged at high tide, causing the land to switch between being a promontory/peninsula and an island depending on tidal conditions. Because of the mystique surrounding tidal islands, many of them have been sites of religious worship, such as Mont-Saint-Michel with its Benedictine abbey. Tidal islands are also commonly the sites of fortresses because of the natural barrier created by the tidal channel.

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