The Wadden Sea National Park is Denmark's largest national park. It covers a total area of 1,459 km2. Most of this area – about 1,239 km2 – is subject to stringent preservation requirements as it were added to the UNESCO World Heritage List in 2014. The Varde Ådal river valley is part of the Wadden Sea National Park. The river valley is, however, not part of the World Heritage-listed area due to specific criteria.
- at The Wadden Sea National Park's website