North Frisian Barrier Island
North Frisian Barrier Island (German: Nordfriesische Außensände, pronounced [ˈnɔʁtˌfʁiːzɪʃə ˈʔaʊsn̩ˌzɛndə], lit. 'North Frisian Outer Sands') is the collective term for three barrier islands (outer shoals) due west of the German Halligen in the North Frisian Islands archipelago. The shoals are a natural breakwater for the Halligen and other islands closer to land.
Source: Wikipedia — North Frisian Barrier Island (CC BY-SA 4.0)