Rura Penthe is an asteroid used as a penal colony by the Klingon Empire, located within 2 sectors of the border to the Federation. It is well-known as "the aliens' graveyard".

The surface temperature of Rura Penthe is extremely low and glaciers dominate the asteroid's appearance. Without proper clothing, no humanoid lifeform is able to survive on the surface, which is why most of the mining facility is underground. A magnetic shield surrounds the mining facility and a vast area surrounding it to prevent prisoners from being transported, but there are no other major security measures, as they are largely unnecessary due to the harsh surface climate.

The asteroid states one of the most important sources of dilithium ore in the Empire. To mine the precious material, a penal colony for both Klingon and alien prisoners was established here, providing sufficient labor force for the extensive exploitation of the asteroids resources.

A part of the Dilithium mine complex on Rura Penthe has been a penal colony of the Klingon Empire since at least the early 22nd century. Banishment to its submontane dilithium mines has since been one of the most feared punishments troughout the whole Klingon Empire and its enemies. It is said, that almost no one survives more than a year in the mines, which does not matter to most of the prisoners as the majority of them are sentenced to a life-long exile.

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