aerial photograph of the Halvergate Marshes on the Norfolk Broads England UK. Taken looking west into the setting sun the image shows South Walsham Marches in the foreground with the low sun angle picking out the numerous drainage channels. in Roman times the area was an open Estuary but since then has silted up. From the 17th century the area has been drained with wind pumps and drainage channels to produce grazing marshes. The area has been protected as a Site of Special Scientific Interest since 1981 and is now recognised as