The following text is from the original listed building designation:
TOWER HILL 1. 5273 (South Side) Tankerton Tankerton Castle TR 16 NW 4/18 II 2. Offices of the Whitstable Urban District Council until 1973. The house is mainly a mid C19 castellated mansion. On the east side it incorporates the small building known previously as Tankerton Tower which was built in 1792, possibly as a beacon with dwellinghouse attached. It consists of a squat octagonal town of 2 storeys, built of flints and red brick with machicolation and a castellated parapet end a small rectangular section of liner elevation to the south. Sash windows with pointed heads. Glazing bars intact.
Listing NGR: TR1119767123

English Heritage, List of Buildings of Special Architectural or Historic Interest (Map). SKE16160.