“Korriban shall be as it always was. A graveyard for the darkest of the Sith Lords, still whispering within their tombs. It shall always be a source of evil, spawning threats throughout the millennia.”
Korriban, originally known as Pesegam, became the home of the Sith and all the darkness it comes with. If, on your own choosing, decide to wander the wastelands and become infused with the ancient Sith lords, you will notice their tombs in a wait of your presence. The dry rocky fissures with hundreds of deep and darkened canyons mark the tombs in the valley of the Dark Lords. The cold winds swirl and hiss at anyone nearby, and the few creatures that live on Korriban include shyracks, dragon-scaled hssiss, and Sith hounds. Are you lucky enough to escape these dangerous creatures? If so, it has been said that Sith alchemy has taken the corpses and transformed them into zombies.
Korriban has been dated back to its beginning in 27,700 BBY. The Rakata invaded the planet intending to harvest slaves so that they could be used for Rakatan projects. The only available resource to survive to this day is the Star Map, which was found around the same time the tomb of Naga Sadow was built. Eventually, the Rakata were forced from Korriban when Sith King Adas led the charge against the Rakatan. Even though Adas perished in the battle, and the Sith society with it. Those involved would later populate on planets such as Arba, Ziost, and Tund, by using the unmanned ships of the Rakatan and leaving Korriban as the graveyard for only the religious astute.
In 7000 BBY, a civil war initiated by Darth Graush left most of Korriban in ruins, and after Dark Jedi arrived a century later, Korriban became an unpopulated repository for increasingly elaborate mausoleums. Burials ceased in 5000 BBY following the Great Hyperspace War, and Korriban remained uninhabited until Exar Kun’s disciples established the Academy there and became the home of the One Sith.
When Darth Revan making Korriban his hub it began to revive the Sith Empire, but the Sith civil war changed all of this and left the planet as a graveyard once more. It has served as training grounds throughout time, but it is more often referred to a ghost town haunted by the secrets of the Sith.
Now the Great Temple stands as a representation of all that is evil. A mausoleum that held the bodies of the deceased Sith Lords, who remain untouched and preserved through the dark side of the Force. Feel free to enter, but do so at your own peril as Tuk’ata hounds prowl the interior to serve as guardians against any raiders or grave-robbers. The Tuk’ata characteristics included sharp horns, long claws and savage teeth. They had high intelligence and could communicate within their own species. Original claims that the Tuk’ata were actually a non-violent grazing animal until Sith alchemy changed their chemistry and transformed them into abominations.
“A cruel planet of rocky red deserts and crumbling ruins, Korriban was the homeworld of the ancient Sith. Reclaimed by the Empire in recent decades, it is now the site of the Sith Academy, where the Dark Council oversees the training of new acolytes. Only Sith may come and go freely from the academy, and for a non-Sith to visit Korriban is a great privilege. Surrounding the academy are the tombs of the first Dark Lords. Used as testing grounds by the academy overseers, the tombs remain filled with traps, monstrosities and relics, even millennia after their construction–along with the bodies of a generation of failed acolytes.”
(H/T – Wookiepedia)