Chelsea was an area of London, located somewhere near Sloane Square. (TV: The Dalek Invasion of Earth) It was presumably located in the Royal Borough of Kensington and Chelsea. (TV: The Church on Ruby Road [+]Loading...{"timestamp":"00:10:53","1":"The Church on Ruby Road (TV story)"})
History
A Dalek landing area was set up at a heliport in Chelsea during their invasion and occupation of Earth in the 22nd century. The First Doctor and Ian Chesterton were taken to a Dalek flying saucer that had landed at the Chelsea heliport after they were captured by a patrol of Robomen. A rescue (TV: The Dalek Invasion of Earth)
References
Once, when asked to consider where the TARDIS had landed, Polly Wright hoped it would be Chelsea in 1966. (TV: The Underwater Menace)
Chelsea 426 was named after the district. (PROSE: The Taking of Chelsea 426)