Cairo

Cairo was a city in Egypt.

History
In 1911, Dr. Warlock, a friend of Marcus Scarman, made some inquiries in Cairo about Marcus. (DW: Pyramids of Mars)

The Seventh Doctor, along with Bernice Summerfield, visited Cairo in 1798. (NA: Set Piece)

Cairo was believed to have been the home of Erimem, a companion of the Doctor from ancient Egypt. (BFA: The Eye of the Scorpion) During an encounter with the plants of YT45, the Doctor saw the fantasy world of his companion, Erimem, as the ruler of an amalgam of the many worlds she has visited along with her home, naming it New Cairo. (BFA: The Mind's Eye)

In an alternate timeline, Area 52 was located in Cairo. (DW: The Wedding of River Song)''

Behind the scenes

 * Nicholas Courtney, who played Brigadier Lethbridge-Stewart, was born in Cairo.