South London derby

South London derby is the name given to a football derby contested by any two of Charlton Athletic, Crystal Palace, Millwall and AFC Wimbledon, the four professional Football Association clubs 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 and Charlton's The Valley 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. AFC Wimbledon play at Kingsmeadow in South West London, eight miles west of Selhurst Park, 11 from The Den and 15 from The Valley. 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.

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. Charlton joined the next year in the 1921–22 season, playing in the same division as Palace and Millwall for the first time. Wimbledon were founded in 1889 and spent the majority of their history as an amateur club, until joining the Football League in the 1977–78 season. In 2003 Wimbledon were relocated to Milton Keynes and reformed as Milton Keynes Dons. In 2002, a new club founded by supporters against this move, AFC Wimbledon, won a rapid succession of non-League promotions to gain Football League status nine years later. AFC Wimbledon played their first derby in 2009, an FA Cup game against Millwall. As of the 2019–20 season, Crystal Palace play in the Premier League, Charlton and Millwall play in the Championship, and AFC Wimbledon play in League One.