Rura Penthe was the sixth planetoid in the Beta Penthe system of the Beta Quadrant.

For centuries, the Klingon Empire used this planetoid as a penal colony. It was widely known as "the alien's graveyard," due to the fact that the life expectancy for a prisoner there was, at most, one year. The prisoners labored at a dilithium mine installation, which existed beneath the surface.

The surface temperature of Rura Penthe was extremely low, the landscape dominated by glaciers and gusting snow. Without proper clothing, warmth, or food, no humanoid lifeform was able to survive for an extended period on the surface (a condition often used to punish prisoners). A magnetic shield encased the mining facility and a vast area surrounding it in order to prevent escape through beaming from the surface. The facility was routinely patrolled by armed guards, but further security measures were deemed unnecessary due to the harsh surface climate.