Seireitei is a circular shiro with four main entrances, ten days walk apart, each guarded by one of the Gatekeepers. These gates are collectively called the Four Great Pure Soul Gates (四大瀞霊門, Shidai Seireimon): these gates are made up of the Northern Black Ridge Gate (黒隆門, Kokuryōmon), the Eastern Blue Stream Gate (青流門, Shōryūmon), the Southern Red Hollow Gate (朱洼門, Shuwaimon), and the Western White Way Gate (白道門, Hakutōmon). The gates are so heavy that it takes the full might of Jidanbo Ikkanzaka to lift one, while during the Bount-led attack on Seireitei, siege machines were needed to open the gates. There are, however, doors within the gates, as seen when Momo Hinamori first entered the Shinigami Academy.
The walls of Seireitei are made of Sekkiseki (Spirit Reducing Stone), a rare type of stone known to negate all Reiryoku, similar to magnetic lodestones. The stone also forms a spherical barrier around the city, extending above and below, stopping anything spiritual from breaching it from ground level, from the sky or from underground.
The wall that surrounds the Seireitei is commonly held up, only closing down when there is an emergency. When it is not down protecting the Seireitei, the wall protects the Soul King Palace, located in an inner dimension.
Information about the Seireitei is confidential. What is known is that in the center of the Seireitei is a white tower known as the Senzaikyu, where criminals are imprisoned; on the hill adjacent to it is the Sokyoku, where prisoners are executed. Those permitted to live in the tranquility of the Seireitei are Shinigami and the Noble Houses. Shinigami live in the Division barracks, while high-ranking officers commute from their own homes.
The majority of the residents of Seireitei, nobility and Shinigami alike, do not interact with the citizens of Rukongai. However, residents of Rukongai, like Renji and Rukia, are allowed to apply for the Shinigami Academy, which is often the only escape from the poorest conditions of Rukongai.