Situated halfway up a mountain, Labyrinthian may be the ruins of an ancient Nord city. Due to the large size of Labyrinthian’s exterior, it contains the entrance to two other dungeons: Shalidor’s Maze and Lost Valkygg. The main dungeon of Labyrinthian itself can be entered via a well-hidden trapdoor at the southern end of the ruins, atop a stone structure.
Labyrinthian can also be accessed via the mysterious Ceremonial Door (appearing to be the main entrance) which is unopenable until the Staff of Magnus quest.
The exterior of Labyrinthian contains four Frost Trolls.