Nordfriesland, the second largest district in Schleswig-Holstein, lies along the North Sea coast. It includes the islands of Sylt, Föhr, Amrum and Pellworm, and the Nordstrand peninsula. Just under 10% of the land within the district has been designated for nature conservation. In 2009, the mudflats of the Wadden Sea were declared a UNESCO World Heritage Site. Nordfriesland’s bracing maritime climate makes it an ideal place for offering therapeutic treatments for respiratory and skin problems. It also has a well-developed tourist industry and is known as a centre of energy production and an agricultural area. The local population includes two sizeable minority groups – the North Friesians and the Danes. As well as standard (High) German, Plattdeutsch, High and Low Danish and Friesian are all spoken there. This makes Nordfriesland the most linguistically diverse district in Germany.