East Lindsey has an area of 1,760 km², making it the fifth-largest district (and second-largest non-unitary district) in England. It was formed on 1 April 1974, under the Local Government Act 1972, from the south-eastern area of the former administrative county of Lindsey. It was a merger of the Municipal Borough of Louth with the Alford, Horncastle, Mablethorpe and Sutton, Skegness and Woodhall Spa urban districts, and the rural districts of Horncastle, Louth and Spilsby, all formerly in the administrative county of Lindsey.