Fething (North Frisian: di / jü Feeding) is a special water storage basin on the Halligen and terps in the marshland on the German and Dutch North Sea coasts. Fethinge are rainwater collecting basins that were usually used as cattle troughs and give the impression of a normal pond. Mostly they were created at the highest point, i.e. in the middle of the Hallig or Terft.
Since the surface water of the meadows and thus possibly also dung could get into Fethinge, they were usually not suitable as reservoirs for drinking water. For this purpose, a separate cistern, the so-called Sood, was created, in which the rainwater from the roofs could collect.
Drinking water was a precious commodity on the Halligen and in the marshland. Due to the island location and the small size of a Hallig, even the groundwater consists of salt water. The Fethinge only lost its task in the middle of the 20th century when the water supply was gradually expanded.
In the meantime, the still existing fethings have been placed under monument protection.
Source: Wikipedia