SANDOWN CASTLE, a block-house in Deal parish, Kent; on the coast, ¾ of a mile N of Deal. It was built in the time of Henry VIII.; comprised central keep orcircular tower, and four surrounding round bastions; was the prison and death-place of Col. Hutchinson; has been undermined by the sea and sold; and is now a ruin.

(John Marius Wilson, Imperial Gazetteer of England and Wales (1870-72))