The South London derby is the name given to a football derby contested by any two of Charlton Athletic, Crystal Palace, Millwall, Sutton United, and AFC Wimbledon, the five professional Football Association clubs that play in the Football League in South London, England. It is sometimes more specifically called the South East London derby when played between Charlton and Millwall. The close geographical proximity of all the teams contributes significantly to the rivalries. Charlton and Millwall are located in South East London, with Millwall's The Den based in New Cross and Charlton's The Valley situated in Greenwich, being less than four miles apart. Crystal Palace are based further south in the suburb of Selhurst, their stadium Selhurst Park being six miles from The Den and eight from The Valley. Since 2020, AFC Wimbledon have been located at the new Plough Lane in Merton, South West London, which is five miles west of Selhurst Park, eight from The Den, and seven and a half from The Valley. Sutton United play at Gander Green Lane in west Sutton, five miles south of Plough Lane and nearly eight miles west of Selhurst Park. According to a 2013 fan survey on football rivalries, Charlton considers their main rival to be Crystal Palace, with Millwall being their second biggest rival. Millwall's main rivalry is with East London club West Ham United, with Palace placed second and Charlton third. Crystal Palace fans consider their main rival to be Brighton, with Millwall second and Charlton third. AFC Wimbledon's main rivalry is with Milton Keynes Dons, with their fans considering Crystal Palace their second biggest rival. Sutton's rivals include AFC Wimbledon and non-league team Bromley. Millwall was founded in 1885, with Palace and Charlton both founded twenty-years later in 1905. The earliest fixture between two of the teams was in 1906 when Crystal Palace and Millwall first met in the Southern League. The two teams have contested the most games, over 130 derbies. Palace and Millwall both entered the Football League in the 1920–21 season.