Slapton Ley is a lake on the south coast of Devon, England, separated from Start Bay by a shingle beach, known as Slapton Sands. It is the largest natural freshwater lake in south-west England being 1.5 miles (2.4 km) long and has two sections; the Lower Ley and the Higher Ley. The site is a National Nature Reserve, a Site of Special Scientific Interest and a Geological Conservation Review site.