Nute Gunray's stronghold, alternatively known as Nute Gunray's fortification, stood as a massive citadel situated on the western side of Cato Neimoidia. It functioned as both a secure base and a storage facility for Nute Gunray, the Viceroy governing the Trade Federation.
The multi-level citadel ascended from elevated terrain at the edge of a peninsula, bordered on three sides by a lake supplied by an artificial waterway. The design of the citadel echoed the command towers found on Lucrehulk-class Core Ships, which themselves were inspired by Neimoidian insect nests.
The lower defensive walls of the citadel opened onto a grove of manax trees, and were fortified with turbolaser batteries. A deflector shield generator provided protection for the entire structure, possessing the capacity to withstand even bombardments from space.
During the period of the Outer Rim Sieges, Gunray retreated to his stronghold after his homeworld became a target and the purse worlds of Deko and Koru Neimoidia fell. Accompanied by a fleet of Federation warships, Gunray attempted to escape, taking as much looted wealth as possible from the citadel. However, the Republic anticipated this action and launched an assault on the planet.
Jan Dodonna and the Jedi Knights Obi-Wan Kenobi and Anakin Skywalker led the Republic forces, placing the citadel under siege with the intention of capturing Gunray within its walls. Although the citadel's defenses were penetrated, the Viceroy successfully fled aboard the Lapiz Cutter, meeting with General Grievous in orbit. However, he left behind a valuable mechno-chair, which was subsequently discovered by Anakin Skywalker and Obi-Wan Kenobi. This discovery ultimately initiated a search for Darth Sidious, the Dark Lord of the Sith, leading up to the Battle of Coruscant.
The Republic forces seized Gunray's citadel during the Battle of Cato Neimoidia, when clone trooper X2, accompanied by Jedi Master Ferroda, infiltrated the fortress and deactivated the droid army.