Dunster Castle the north; a third force, under the command of William de Mohun, landed by sea along the Somerset coast. William had been granted 68 manors in the region and by 1086 had established a castle at Dunster; this would form both the "caput", or principal castle, for his new lands, and help guard the coast against the threat of any fresh sea-borne attack, as well as controlling the coastal road running from Somerset to Gloucestershire. This first castle was a motte and bailey design, built upon the former Anglo-Saxon "burgh"; the top of the Tor was scarped to form the
Dunster Avill, offering a natural defence and making the village an inland port. Nearby is the Dunster Park and Heathlands Site of Special Scientific Interest noted for nationally important lowland dry heath, dry lowland acid grassland, wood-pasture with veteran trees and ancient semi-natural oak woodland habitats. The fauna of the lowland heath includes the heath fritillary ("Mellicta athalia"), a nationally rare butterfly. The assemblage of beetles associated with the veteran trees is of national significance because of the variety and abundance of species. Along with the rest of South West England, Dunster has a temperate climate which is generally wetter and