Within the Sith's first century of their retreat to Dromund Kaas they constructed Kaas City deep in the jungle, a testament to reestablishing the grand Imperial society lost in the Great Hyperspace War, and a mighty citadel in the center of the city which was known to house the Emperor and his Dark Council.
As the center of Imperial government, the citadel contained the headquarters of the Ministries of War, Intelligence, and Logistics. The citadel was also home to a Mandalorian embassy of sorts, known as the Mandalorian enclave.
The Great Hyperspace War Bas-Relief in the Emperor's chambers.
In 3678 BBY, the Great Hyperspace War Bas-Relief, or a similar rendering of it, was displayed along the wall of the Sith Emperor's chambers.
The Imperial Citadel on Dromund Kaas had two separate incarnations. The first one's construction began shortly after the Exile fleet's arrival on the planet in 4980 BBY. The original structure resembled both the Sith Academy on Korriban and the Sith Citadel on Ziost. Before it could be constructed, however, the land upon which the Citadel and Kaas City itself had to be cleared of not only thick jungle, but a host of fearsome creatures that made Dromund Kaas so dangerous. Odile Vaiken, future father of the Imperial Navy and first Grand Moff of the Empire, reportedly slew a rabid terentatek on the site where the Citadel would later stand. It served as the seat of the Empire until it was destroyed in 4043 BBY during the Kaggath fought between Darth Qalar and Darth Victun. The two Sith Lords were executed by the Dark Council, and Darth Nostrem was chosen to oversee the citadel's reconstruction.
The second citadel was designed by the Sith Emperor himself and differed greatly from the first. It was no longer modeled after the earlier citadel designs. After its construction, Darth Nostrem was locked in its depths in order to test the citadel's new labyrinthine defenses. The Sith Lord never escaped and eventually died.
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