​SOUTHGATE, an urban district in the Enfield parliamentary division of Middlesex, England, 9 m. N. of St Paul's Cathedral, London, on the Great Northern railway. Pop. (1901), 14,993. It is pleasantly situated in a wooded district, and forms an outer residential suburb of the metropolis. Christ Church, in Early English style, is the work of Sir Gilbert Scott, and contains stained glass windows from the designs of Sir E. Burne- Jones and D. G. Rossetti. Close to New Southgate station is Colney Hatch Lunatic Asylum for the county of London, opened in 1851 and subsequently much enlarged.