Halligen

The Halligen or the halliger are small islands without protective dikes. There are ten German halligen in the North Frisian Islands on Schleswig-Holstein's Wadden Sea-North Sea coast in the district of Nordfriesland and one hallig at the west coast of Denmark .
The name comes from a Celtic word hal, meaning "salt", a reference to the low-lying land in the region which is often flooded over with saltwater by the tides. A greater number of Halligen existed in the Middle Ages than in the 21st century. The very existence of the Halligen is a result of frequent floods and poor coastal protection. The floods were much more common in the Middle Ages and coastal protection was much poorer. A look at the maps on this page will demonstrate that this part of the North Sea coast is very much at the sea's mercy.

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