The Caverns of the Hidden One represented a network of subterranean chambers located far beneath the surface of the planet Dorin. This cave system served as the home for the Hidden Ones, a clandestine division of the Baran Do—a Force-sensitive organization native to Dorin—whose purpose was the safeguarding of the Baran Do's accumulated wisdom.
These caverns were initially discovered and then expanded upon by the male Kel Dor Baran Do Master named Tokra Hazz, an event that occurred shortly following the conclusion of the Great Jedi Purge. Hazz, concerned that the Sages might face annihilation by the emerging Empire similar to the fate of the Jedi Order, secretly established the Hidden Ones. This covert group within the Baran Do was tasked with preserving the Order's knowledge, ensuring that, should the Baran Do be destroyed, the Order could be re-established. He assumed the role of the sect's first leader, known as the Hidden One, and is believed to have originated the dying ceremony as a method for individuals to join the sect.
In the year 43.5 ABY, Luke Skywalker, the recently exiled Jedi Grand Master, journeyed to Dorin alongside his son, the Jedi Knight Ben Skywalker, with the intention of engaging in conversation with Koro Ziil, the Baran Do Master of the Order. Their travels eventually led them to the Caverns of the Hidden One, where, after Luke dueled Koro Ziil, they successfully persuaded the Hidden Ones to abandon their subterranean refuge and return to the planet's surface.