Djamonkin Crater was the human name for a location on Earth in approximately 100,000 BCE. The crater was flooded, with a small island in the center, known to locals as "Djamonkin Augh," meaning "Big Man's Water." The waters surrounding the island were populated by merse, which were likely transplanted there from their homeworld by the The Librarian. The island itself was uninhabited, but in the center was located a Forerunner Cryptum belonging to the Ur-Didact. Hidden in the central peak was a design seed for a ship later used by the Didact to escape. The artifact site was surrounded by a baffler, probably to discourage curious humans.
Riser's families' geas made them spend many generations trying to penetrate the baffler and reach the area inside. Around approximately 100,000 B.C.E, however, it was visited by Bornstellar-Makes-Eternal-Lasting, along with Chakas and Morning Riser. With their help, Bornsteller breached the baffler and found the Didact's Cryptum within.
- Halo: Cryptum (First appearance)