Mar de Frisia (Schleswig-Holstein)

The Schleswig-Holstein Wadden Sea National Park was approved by act of the regional parliament on 22 July 1984, with effect from 1 October 1985, and was significantly enlarged in 1999. At 4,410 km² it is by some way the largest national park in Germany and the largest in Europe between the North Cape and Sicily. Some 68 % of its area is permanently under water and 30 % falls dry periodically with the tide; the land portion is mostly salt marsh.

It runs from the maritime border with Denmark in the north to the mouth of the Elbe in the south. Together with the Lower Saxony park, the Hamburg park and some unprotected stretches of the Elbe estuary it forms the German part of the Wadden Sea, which along with the Alps is the last great expanse of wilderness in Europe.

Since 1990 the park has formed, together with the North Frisian Halligen, the Schleswig-Holstein Wadden Sea and Halligen Biosphere Reserve, recognised by UNESCO. The Halligen are low islands without dykes that flood several times a year: five of them — Langeneß, Oland, Gröde, Nordstrandischmoor and Hooge — with some three hundred inhabitants, joined the reserve voluntarily in 2005 and make up its development zone. In 2009 the Wadden Sea was inscribed on the World Heritage List along with the Dutch and Lower Saxon sectors; in 2011 the Hamburg Wadden Sea was added, and in 2014 the Danish Vadehavet park. The whole totals 11,434 km², of which some 7,640 lie in Germany.