Great Library of the Jedi
located on the planet Ossus, this vast library was conceived by Jedi Master Odan-Urr, who oversaw its construction some 4,000 years before the Battle of Yavin. Designed to be a repository of all known information about every sentient endeavor, the Great Library encompassed the Chamber of Antiquities, which preserved paper documents from the earliest days of the Jedi Knights. It was Master Odan-Urr's belief that all information, no matter its source, could potentially be of use to the Jedi Order, so even the dreaded Sith holocrons were stored in its vaults. The Great Library was thought to have been lost during the Great Sith War, as Ossus itself was swept clean in the cataclysmic conflict. It wasn't until Executor Sedriss discovered its existence, several years after the Battle of Endor, that its chambers were reopened. Since then, the Great Library has been controlled by the new Jedi Knights training under Master Luke Skywalker. Much of its contents remain a mystery, but Master Skywalker was hopeful that the knowledge it contained would again be revealed to the galaxy. Mirroring the architecture of the Jedi Temple on Coruscant, the Great Library was divided into four towers, each holding a different era's worth of information. Master Odan-Urr categorized the information as Pre-Hyperdrive, Pre-Republic, Early Republic, and Modern Republic, although the Jedi of Master Skywalker's time have had to adapt their investigations to a more upt-o-date classification.