Originally, the world once within the domain of the System Lord Bastet and populated by her followers where it was mined for its rich deposits of Trinium. Whilst an idealic lush and fertile world, the planet succumbed to a devastating natural disaster which rendered it an unlivable wasteland that was dominated by a toxic fog as well as noxious gases. Once the native life died, the remaining inhabitants were forced to flee the planet and seemingly forever leave it a dead world. Whilst other Goa'uld abandoned any thought of taking this planet, it was Heru'ur who decided to embark on an ambitious project to incorporate it along with its rich mineral deposits as his own. In order to adequately take this planet, he recruited the assistance of a number of Goa'uld scientists in order to create the city of Letopolis from which the world took its name. This floating city consisted of a network of interconnected platforms which hovered above the toxic fog by use of anti-gravity technology thus allowing its residents to escape from the deadly gases.
Using the city, he managed to use it as a platform to regain control of the remaining trinium mines on the surface. Letopolis was also staffed by the very best of Heru'urs Horus Guard and became a major centre of power for the System Lord. (RPG: "Living Gods: Stargate System Lords")