CLACTON-ON-SEA, a watering-place in East Essex, Eng land; 71m. E.N.E. from London by a branch from Colchester of the L.N.E.R. Pop. of urban district (1931) 15,851. Clay cliffs of slight altitude rise from the sandy beach and face south-east ward. In the neighbourhood, however, marshes fringe the shore. The church of Great Clacton, at the village 12m. inland, is of Norman and later date. It is an important watering-place for London and the suburbs, with convalescent homes and sanatoria.