The nightmare corpse-city of R'lyeh lies deep under an ocean on the planet Earth. It is the domain of dread Cthulhu, who lies slumbering at the heart of the sunken city, held in stasis by the Elder Sign. At times, R'lyeh rises to the surface and the doors of Cthulhu's tomb open, allowing him to awaken and roam the city for a limited time.
- R'lyeh was created by real-world author H.P. Lovecraft in his short story "The Call of Cthulhu".
- James Jacobs. (Apr 30, 2013.) Is R'lyeh on Earth?
- Dennis Baker et al. (2013). Pathfinder RPG Bestiary 4, p. 139. Paizo Publishing, LLC. ISBN 978-1-60125-575-4
- James Jacobs. (2011). Cults of the Dark Tapestry. Wake of the Watcher, p. 64. Paizo Publishing, LLC. ISBN 978-1-60125-311-8