Westcliff-on-Sea is a suburb of the city of Southend-on-Sea, located within the ceremonial county of Essex, England. It is on the north shore of the lower Thames Estuary, about 37 miles east of London. The Westcliff-on-Sea area is described by Southend-on-Sea City Council as having a border in the east with Milton Road, Hamlet Court Road and Gainsborough Drive; Prittlewell Chase to the North and Valkyrie Road/ London Road/ Southbourne Grove in the west.