The North Devon Coast was designated as an Area of Outstanding Natural Beauty in September 1959. The AONB contributes to a family of protected landscapes in the Southwest of England and a total of 38% of the region is classified by the International Union for the Conservation of Nature as Category V Protected Landscapes. The twelve Areas of Outstanding Natural Beauty extend to 30% of the region, twice the proportion covered by AONBs in England as a whole and a further two National Parks, Dartmoor and Exmoor, cover an addition 7%.The North Devon Coast AONB covers 171 square kilometres (66 sq mi) of mainly coastal landscape from the border of Exmoor National Park at Combe Martin, through the mouth of the Taw & Torridge Estuary to the Cornish border at Marsland Mouth. The dune system at Braun