- For the individual of the same name, see Sarn.
Sarn was a volcanic planet which at one point was a colony of Trion. The Trions mainly used Sarn for its regenerating Numismaton Flame, but over time the Trions neglected Sarn and began using it as a dumping ground for political prisoners.
The people of Sarn descended from what was a relatively high-technology society into tribalism and superstition. They worshiped Logar God of the Fire Mountain, and sacrificed unbelievers in fire.
When Turlough and the Doctor went to Sarn, Turlough sent a distress call to Trion, requesting assistance for the people of Sarn, who were threatened by a volcanic eruption. (DW: Planet of Fire)