The Soul King Palace consists of several layers, with one layer suspended above the other. The lowest level is comprised from many buildings of the same style to that ofSeireitei. From this, a large stairway leads upwards to a wide and flat expanse, with both areas at the base and top of these stairs being lined by rows of huge, circular pillars. Floating above are five discs with numerous buildings on each, while suspended higher still is a large cylindrical structure that has a conical top and bottom.
The sekkiseki walls that surround Seireitei are ordinarily intended to protect the Soul King Palace, instead meant only to fall down to Seireitei in times of emergency. However, if emergencies occur in succession, they remain in place around Seireitei indefinitely until things are returned to normal.
The Soul King Palace is further protected by 72 barriers between it and the Seireitei. Should these barriers be forced open via clothing constructed from an Ōken, they cannot be closed off for 1 hour and 40 minutes due to the sheer defensive power of the clothing
There exist a group of elite guards known as "Divine Soldiers" (神兵,Shinpei) which are led by Senjumaru Shutara. Each guard wears a blackhakama with a gray sash tied around their waist and a black mask with four light-colored lines tracing over their heads, and their hair is tied into a long spike at the back of their head before being left to hang free about halfway through the length. They are all armed with swords.
There is a much more powerful version of these soldiers known as a"Second-Class Divine Soldier" (二級神兵, Nikyū Shinpei), which Senjumaru refers to as the "Shield of the Soul King" (霊王の盾, Reiō no Tate). It resembles an ordinary soldier, but is extremely large and wears a circular black hat on its head. The backs of its wrist each have one-half of a large, black, circular shield on them.
After absorbing the Soul King, Yhwach drastically altered the appearance of the Soul King Palace, most notably by bringing the Wandenreich city to the palace and placing the main palace at ground level while covering parts of it with ice. He also connected the five floating cities nearby to the Wandenreich city, thus creating a massive Quincy Zeichen, and formed a massive, tower-like palace with Silbern on the top for his new stronghold, which he calls the Wahrwelt (真世界城 (ヴァールヴェルト), Vāruveruto; German for "True World", Japanese for "True World Castle") because it will be the cornerstone of his new world. One of the five branches forming the city is known as the Zwei Ast (2番枝街 (ヅヴァ・アスト), Zuvai Asuto; German for "Second Branch", Japanese for "Second Branch City")
The route to the inner dimension in which the palace resides can only be opened with "a key", fittingly named the Ōken (王鍵, Royal Key), the location of which is kept secret, only being passed down verbally from one Gotei 13 Captain-Commander to the next. There are only two ways to enter the Spirit King Palace:
- With the permission of the Royal Guard. They don't have to be there physically, they only need to want the person to enter.
- Make a Royal Key by creating a Royal Guard.
A Royal Guard can also open up a Chōkaimon (超界門, Super World Gate) to send someone directly to the human world, and use the same gate to send said "someone" back, but to do so requires syncing the arrival and departure times.
The only known method to get from section to section of the Soul King Palace is to be catapulted into the sky, in the direction of the intended destination
The Royal Guard, also known as the "Zero Division", are the protectors of the Soul King Palace and its residents, particularly the Soul King. Though they commonly remain within the palace, when the Royal Guard do need to travel, their preferred method of transportation takes the form of a huge pillar called the Tenchūren(天柱輦, Heavenly-Pillar Palanquin). While this pillar is able to freely exit the inner dimension, it is unable to return to the palace on its own and is instead entirely reliant on outside assistance to do so, such as Kūkaku Shiba's Kakaku Hō (花鶴砲, Flower Crane Cannon).