and Wales' largest natural lake. The area is steeped in culture and local history, where more than half its population speak Welsh Fossil shell fragments on the summit of Snowdon date from over 500 million years ago and the ancient ‘Harlech Dome’ of which Snowdon and Cadair Idris form the northern and southern extents respectively, was created in the Cambrian Period before the volcanoes erupted. The more recent Ice Age glaciers were at their peak 18,000 years ago in Snowdonia and formed the distinctive U-shaped valleys including Llanberis and Nant Gwynant in the north and Tal-y-llyn Lake in the south. The park is governed by the Snowdonia National Park Authority, which is made up of local government and Welsh Government representatives, and its main offices are at Penrhyndeudraeth. Pembrokeshire Coast Formed in 1952, this is the only national park recognised primarily for its coastline; it covers almost all the Pembrokeshire Coast, every offshore island, the Daugleddau estuary and large areas of the Preseli Hills and the Gwaun Valley. It is an ecologically rich area recognised as of international importance for a wide range of high quality habitats and rare species. The park contains thirteen Special Areas of Conservation, five Special Protection Areas, one marine nature reserves and seven national nature reserves as well as sixty Sites of Special Scientific Interest. The park also contains a wealth of human history and culture, including the UK's smallest city, St Davids and Iron Age forts. Within the park there are also a total of sixty geological conservation sites ranging from small roadside quarries and isolated crags on hilltops to many kilometres of coastline. The Park is managed by Pembrokeshire Coast National Park Authority, which has around 130 staff and a committee of 18 members. The Chief Executive is Tegryn Jones. The Authority also manages the entire length of the Pembrokeshire Coast Path, a national trail which lies almost entirely within the Pembrokeshire Coast National Park. More than 26,000 people live within the park. 58.6% of the population could speak Welsh in 2011. Brecon Beacons The last of the three national parks, formed in 1957, the park straddles the divide between rural mid Wales and industrial South Wales. It stretches from Llandeilo in the west to Hay-on-Wye in the northeast and Pontypool in the southeast, covering and encompassing four main regions – the Black Mountain in the west, Fforest Fawr and the Brecon Beacons