Chesil Beach (also known as Chesil Bank) in Dorset, England is one of three major shingle beach structures in Britain. Its name is derived from the Old English ceosel or cisel, meaning "gravel" or "shingle". It runs for a length of 29 kilometres (18 mi) from West Bay to the Isle of Portland and in places is up to 15 metres (50 ft) high 200 metres (660 ft) wide. Behind the beach is the Fleet, a shallow tidal lagoon. Both are part of the Jurassic Coast and a UNESCO World Heritage Site, and together form an SSSI and Ramsar Site.