Central 46 Compound

The Building is a highly restricted area in the Seireitei in Soul Society that serves as the headquarters of the Central 46.

Overview
Most of the building is underground, with only a small portion visible from the surface. In the anime, it was depicted as a circular building in the center of a body of water, surrounded by a wall with a single gateway. Access to the main building was via a bridge. It houses the Central 46, the central government of Soul Society. The Central 46 rules Soul Society on behalf of the Spirit King. They make all of Soul Society's laws and try those who are charged with breaking them, whether the crime was committed in Soul Society or in the Human World. Following the massacre of the Central 46 at the hands of Sōsuke Aizen during the Soul Society arc, and Genryūsai Shigekuni Yamamoto subsequently taking over their normal duties, the compound has lost much of its former status as one of the most important places in Seireitei.

Underground Assembly Hall
The Underground Assembly Hall is where the Central 46 meets. It is an octagonal structure located in a large open space within the main building, and was also referred to as the Diet Building. Beyond the entrance to this structure there is a staircase leading down into the hall. The benches and high-backed chairs of the 40 wise men are arranged in two concentric rings, one higher than the other, surrounding an open area. In the walls there are recesses with stairs leading up to them, where the six judges are seated. There are large banners on its walls. It has thirteen levels of protection to keep out or at least stall intruders. During Aizen's rebellion, the Assembly Hall was placed under lock down.

Notable events to occur in the Assembly Hall are the massacre of the Central 46 by Aizen, the manipulation of Rukia Kuchiki's execution, the trial of Kisuke Urahara, which took place 101 years before the start of the story, and the sentencing of Sōsuke Aizen. On this occasion, the members of the Central 46 sat behind numbered screens to maintain their anonymity. The Hall was kept in darkness during the trial, with the only lights shining upon Urahara and his co-accused, Tessai Tsukabishi.

Seijōtōkyorin
The is where the Central 46's members reside. It is the only place in all of Seireitei that is completely off limits to all except the Central 46, no matter what reason they may have. The residences are tall, thin tower-like buildings with the entrance raised off of the ground and accessed via a short stairway, with a wooden walkway surrounding the building. There is a tall, narrow window in the wall starting just above the door that continues to the top of the tower. Little of the interior is seen beyond the entrance, with no furnishings visible. It is unknown if there is only one floor, or if there are multiple levels inside the towers. Although it is unconfirmed, the area being referred to as a forest suggests that there are likely 46 of them. It is not revealed if there is a difference between the residences of the wise men and the judges.

Notable events to occur here are the reunion of Aizen and Momo Hinamori, and the confrontation between Aizen and 10th Division Captain Tōshirō Hitsugaya.

Daireishokairō
Also known as the is a repository of all the knowledge and history of the Soul Society. This is another area to which access is restricted. As a result, few are familiar with its inner workings even among the captains. Ukitake was placed in charge of investigating the library's circuits to identify anything that Aizen may have researched during the time in which he was believed to be dead. Ukitake's investigation discovered that Aizen had accessed much data on the Hōgyoku and the King's Key.