Kaldor

Kaldor was a desert planet colonised by humans for the many minerals in its sands, among which were zelanite, keefan, and lucanol (which was most prized).

The only known structure on the planet was Kaldor City, populated by humans with sandminer robot servants that tended to their whims and also helped manage the sandminers themselves.

The Fourth Doctor and Leela once visited the planet and became involved in a plot to make the robots kill all humans. (TV: The Robots of Death)

Centuries after the colonisation of Kaldor, an UV-1 robot began to reprogram Super-Vocs to turn them against humans, but this was plan was stopped. (COMIC: Crisis on Kaldor)

Behind the scenes

 * In the book Doctor Who: 100 Scariest Monsters, Kaldor is misspelled Caldor.
 * The comic Crisis on Kaldor has the Doctor stating the planet's name to be Kaldor, while the name was previously only thought to be applied to the city.