Mobile Castle
From Tardis Wiki, the free Doctor Who reference
The Mobile Castle was a castle on Trion built out of non-Trion rock. It was thirty metres high and, despite its name, did not move even during the quake that shook the Sacred Temple, a nearby structure that was built at the same time. A door was kept open through a gravity shield. (PROSE: Turlough and the Earthlink Dilemma)
