Mongolia

Mongolia was a country in Asia north of China.

In the Cretaceous period, Mongolia was populated by dinosaurs, such as tsintaosaurus, dsungaripterus, protoceratops, velociraptor, ankylosaurs, tyrannosaurs, bactrosaurs and Alioramus. The Seventh Doctor arrived in Mongolia during the Cretaceous period to pick up Ace, whom he had dropped off there. Along the way he encountered a pit of dholes and an alien slave who had escaped from a nearby construction site. Ace arrived with a herd of dinosaurs to trample the site, destroying it and freeing the slaves. (PROSE: Living in the Past)

A Raxacoricofallapatorian arm, believed by Rose Tyler to belong to a Slitheen, was found in Mongolia in 1952. It ended up in the Vault, an installation owned by Henry van Statten which was located 50 floors underground near Salt Lake City, Utah. (TV: Dalek, GAME: The Last Dalek)