Backrooms Level 33, also known as the bottomless and topless chasm...
The ancient Bridge Keep once stood at the entrance of a vast Chasm kingdom. Now run down, and falling apart, it hosts at least one noclip point. Entities and doleful creatures roam the keep's halls and passage ways.
Travels claim vast networks of tunnels and caves riddle the Chasm's cliffs, all connected to Bridge Keep.
The Howling Knight often rescues travels who accidentally noclip into the keep, bringing them to more civilized and safe regions.