The Witch House, Arkham

The garret room where the witch Keziah Mason once lived, its walls meeting at angles that don't sum the way a normal room's should. Sleeping there is reportedly the easiest way to leave Arkham without ever changing address.

Whereabouts: A run-down boarding house in Arkham, Massachusetts, kept standing mainly because no builder wants to touch its top-floor garret.

Access: By renting the room outright — Gilman takes it specifically because of its history and its below-market rent, both explained by the same reputation.