The El Raja Key is one of the massive abandoned siege castles found in the Cairnlands outside the walls of the city of Absalom. It was first catalogued for the Pathfinder Society in 4323 AR by the legendary Durvin Gest, and was known to have been explored by Venture-Captain Shevala Iorae, who recorded her findings in Volume 56 of the Pathfinder Chronicles.
- El Raja Key was originally designed by the great Robert J. Kuntz for his campaign and incorporated into the original Greyhawk campaign that he and Gary Gygax ran. In that campaign it became Castle Greyhawk.
- James Jacobs et al. (2011). The Inner Sea World Guide, p. 41. Paizo Publishing, LLC. ISBN 978-1-60125-269-2
- Tim Hitchcock, Erik Mona, James L. Sutter, and Russ Taylor. (2009). Seekers of Secrets: A Guide to the Pathfinder Society, p. 27. Paizo Publishing, LLC. ISBN 978-1-60125-178-7
- Erik Mona. (2007). Opening Moves (Pathfinder's Journal). Burnt Offerings, p. 85. Paizo Publishing, LLC. ISBN 978-1-60125-035-3