Cave-Under-Tree was the name given by the Esh-kha species to a subterranean facility built by the Rakata underneath a massive zedalus tree in the Tomb, an ancient prison on the planet Belsavis. When the Esh-kha were released from their imprisonment during the invasion of Belsavis, they captured the powerful Sith Lords known as the Dread Masters, and they moved the Sith to the Cave-Under-Tree. There, the Esh-kha Heart Rend and his savants sought to harness the Dread Masters' power, but were defeated by Imperial forces that freed the Dread Masters.