The cavern was built by the Tarasin over one hundred years before the Clone Wars and they used it to imprison the t'salak, a dangerous creature that had attacked them. They put a series of obstacles inside it, to prevent anyone with malicious intent from freeing the creature.
During the Clone Wars, a group of workers from CreedCon Construction accidentally rediscovered the cavern while constructing a race course. The Dark Jedi Raik Muun entered it and hoped to free the t'salak. She passed most of the obstacles, but could not pass the final one, which could only be achieved by a Force-user who had not been tainted by the Dark side of the Force.