Titan Base

Titan base was a large filling station that existed on Titan in the early 51st century. It had a crew of four, three of which worked in shifts, arriving on the base by Titan shuttle and then staying until a relief crew arrived. The fourth crew member was the commander, who seems to have been a permanent inhabitant of the base.

In the year 5000 Titan Base was taken over by the Swarm when an infected relief crew arrived. They wanted to turn the base into a Hive. The Fourth Doctor ignited fuel tanks in the base, which coupled with methane in the air; the moon was destroyed. (DW: The Invisible Enemy)