Gaitenkyūden

is one of the five cities located in the Royal Palace. Like the other cities in the dimension, it sits upon one of five tremendous disks and is ruled by a member of the Royal Guard; namely, Taira Geshunin.

Overview
Unlike Tenkyūden, the city ruled by Raian Getsueikirite, a fellow member of the Royal Guard, Gaitenkyūden is more modernistic. While it retains similar structures to the Rukongai, it also has skyscrapers more akin to those found in the modern World of the Living.

Gishososai
The city is known for the, an archive on "almost everything", in the words of Taira, that has transpired since the beginning of time. It contains even more records and knowledge than the in Soul Society. Raian Getsueikirite once brought Seireitou Kawahiru, Mashū Getsueikirite, and Shiori Miyamoto here to learn about the three treasures of the King of Souls. Not only did the archives have information on them, but it also contained information as to their whereabouts, whereas the Daireishokairō didn't so much as mention them.

Trivia

 * The word "gaiten" (外典) stands for the Greek word "Apocrypha", which means "those hidden away". It is a term usually applied to hidden or forbidden knowledge.