Wales has three designated national parks. Snowdonia National Park in northwestern Wales was established in 1951 as the third national park in Britain, following the Peak District and the Lake District. It covers of the mountains of Snowdonia and has of coastline. The Pembrokeshire Coast National Park was established the following year to protect the spectacular coastal scenery of West Wales. It includes Caldey Island, the Daugleddau estuary and the Preseli Hills, as well as the entire length of the Pembrokeshire Coast Path. The Brecon Beacons National Park was established five years later and extends across the southern part of Breconshire, the northwestern part of Monmouthshire and parts of eastern Carmarthenshire. In each case, the park authority acts as a special purpose local authority and exercises planning control over residential and industrial development in the park. The authorities have a duty to conserve the natural beauty of the area, and to promote opportunities for members of the public to enjoy and appreciate the park's special qualities.