Foul Bay is a 3 km long, open west-facing bay bordered by Knobby Head and White Cliff Point. In between is 4 km of irregular rocky shoreline dominated by granite in the south and calcarenite in the north. It contains seven small beaches, all backed by generally well vegetated rising dunes, extending 1.5-2.5 km inland to the Caves Road. While the bay faces west the shore is moderately sheltered by a series of reefs extending 2 km south of Hamelin Island to South West Rock. There is access to either end via the Cosy Corner Road in the south and the Cape Hamelin Road to the north. The Cape to Cape walking track runs through the vegetated dunes behind the southern half of the bay and follows the shoreline along the northern beach.