The tomb of Darth Bane was built inside the former Sith Academy on Korriban to house the remains of the Dark Lord of the Sith Darth Bane, who died almost a millennium before the Clone Wars. A colossal statue of Bane in his Sith armor was erected at the far end of the massive burial chamber. Bane's stone sarcophagus served as a secret entrance to a chamber used by the ancient Sith to sacrifice Jedi.
Sometime around 20 BBY, Jedi Grand Master Yoda traveled to Korriban and entered the tomb of the long deceased Bane. Bane awoke, appearing as a giant, smoldering specter out of his sarcophagus, and challenged Yoda, asking whether the Jedi had come to learn as his apprentice. Yoda said that Bane was an illusion, at which point the specter disappeared into the sarcophagus.
Bane's body had been obliterated when he failed to take over the body of his apprentice, Darth Zannah, and his spirit was consigned to Chaos, leaving just his arm which had been cut off shortly before his death.