New Adasta served as the main population, commercial, and political hub of the re-established Sith, and it was also the original capital of the ancient Sith Empire located on the planet of Ziost. This sprawling metropolitan city was built on top of a rugged rock formation within Ziost's tundra, and the Central District was uniquely situated inside a cave beneath the rock. At the city's heart stood the People's Tower, a towering skyscraper with a design reminiscent of the Imperial Citadel. During the Invasion of Ziost, Vitiate, the former Sith Emperor, concentrated much of his might and focus on New Adasta as he dominated the planet's inhabitants.
Sometime between the Great Hyperspace War and the Great Galactic War, during a period when the Sith were recolonizing and reclaiming territories lost in the earlier war, New Adasta was erected by the Sith. In the years that followed, it evolved into a significant urban center, supplanting the planet's previous capital and becoming the primary Sith nexus in the Imperial Space borderlands. Although the Sith Empire's new capital was now situated on the jungle planet Dromund Kaas, the construction of New Adasta restored a considerable amount of Ziost's prior importance.
Beyond its strategic importance as a border colony, New Adasta also functioned as one of the Empire's most prominent trade centers, drawing merchants from across the Empire to its bustling commercial areas. As such, it was highly regarded as one of the most vital economic hubs in the entire Empire, which even led to the planet being called "the Gateway to the Empire."
At some point in time, the headquarters for the Ministry of Logistics was moved to this major city, with its minister establishing an office at the Orbital Defense Command Center, which served as the planet's capitol building.
The city also housed the Empire's main customs office and at least one hotel.
In 3640 BBY, SIS operative Theron Shan and Jedi Master Gnost-Dural made their way to the city during Operation End Game. There, with assistance from his associate Teff'ith, Shan successfully stole a black cipher from Minister Davidge's vault within the heavily guarded Orbital Command Center. This cipher enabled the Galactic Republic to easily engage in counter-espionage operations against Imperial Intelligence.
New Adasta made its first appearance in the 2012 novel titled The Old Republic: Annihilation. The city was not officially given a specific name at that time, and it was only referred to as "Ziost" in the novel. It was later showcased in Game Update 3.2: Rise of the Emperor, which provided the city with its proper name. Facebook posts from the official Star Wars: The Old Republic account confirmed that these were the same location by quoting Gnost-Dural's description of the city.