Planet (The Ribos Operation)

The White Guardian summoned the Fourth Doctor to a planet where he assigned him the task of collecting the segments of the Key to Time. The immediate area appeared as rocky desert with dead trees and a cream sky. The planet was 116 parsecs from Ribos. (TV: The Ribos Operation)

According to another account, the Guardian met with the Doctor in a garden filled with orchards, fountains, and birds chirping. When the meeting was done, the area dissolved into amber light and the Doctor was almost left in the black void of space, barely making it to his TARDIS before the doors were sucked shut by the vacuum. (PROSE: Doctor Who and the Ribos Operation)