Cairo

Cairo was a city in Egypt.

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

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

Cairo was the home of Erimem, a companion of the Doctor from ancient Egypt. (AUDIO: The Eye of the Scorpion) In Erimem's Kyropite-induced dream on YT45, she was the ruler of New Cairo, an amalgam of her home and the many worlds she has visited. (AUDIO: The Mind's Eye)

In an alternate timeline where all of history happened at the same time, the train to Area 52 stopped off at Cairo. (TV: The Wedding of River Song)

Behind the scenes

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