Hierarchical City

A Hierarchical City (階層都市) is a term used to describe cities that were built after the Dark War by the Novus Orbis Librarium. There are 23 hierarchical cities known thus far.

Information
After the Dark War, which left a large amount of hazardous seithr that covered the world, a lot of humans and animals became tainted with the seithr and died off. Humans were forced to move to high altitude, mountainous areas where concentration of seithr is lesser. Hierarchical Cities exist around the world in various regions, and each one is assigned a number. The highest placed Hierarchical City is the first, the lower it is, the higher the number of the city. In each hierarchy are many cities, towns, villages. The upper level contains the Librarium branch office, while the higher layers are reserved for the wealthy, Librarium personnel, and collaborators. The poor, refugees, and other indigenous races live in the lower layers.

Weather in the cities is maintained by the weather control device, and they are also surrounded by a special barrier. Its properties are unknown, but according to Hakumen, it's similar to the Ishana's barrier.

People travel between cities by aircrafts, which are monitored by the Librarium. Some exceptions are Ikaruga Federation cities, as they're so close to each other that people can travel between them by trains safely.

Each of the Hierarchical Cities have a Cauldron deep within.

Hierarchical Cities

 * The 0th City of Izanagi (第零都市「イザナギ」)
 * The 1st Hierarchical City of Ōkoto (第一階層都市「オオコト」)
 * The 2nd Hierarchical City of Iwatsuchi (第二階層都市「イワツチ」)
 * The 3rd Hierarchical City of Iwasu (第三階層都市「イワス」)
 * The 4th Hierarchical City of Naobi (第四階層都市「ナオビ」)


 * Ikaruga Federation (イカルガ連邦)


 * The 5th Hierarchical City of Ibukido (第五階層都市「イブキド」)
 * The 6th Hierarchical City of Yabiko (第六階層都市「ヤビコ」)
 * The 7th Hierarchical City of Kazamotsu (第七階層都市「カザモツ」)
 * The 8th Hierarchical City of Wadatsumi (第八階層都市「ワダツミ」)
 * The 9th Hierarchical City of Akitsu-Kō (第九階層都市「アキツ―甲」)
 * The 10th Hierarchical City of Akitsu-Otsu (第十階層都市「アキツ―乙」)


 * Izumo Region (イズモ地方)


 * The 11th Hierarchical City of Shinatsu (第十一階層都市「シナツ」)
 * The 12th Hierarchical City of Kukunochi (第十二階層都市「ククノチ」)
 * The 13th Hierarchical City of Kagutsuchi (第十三階層都市「カグツチ」)
 * The 14th Hierarchical City of Nozuchi (第十四階層都市「ノヅチ」)
 * The 15th Hierarchical City of Torifune (第十五階層都市「トリフネ」)


 * The 16th Hierarchical City of Ōgetsu (第十六階層都市「オオゲツ」)
 * The 17th Hierarchical City of Yamatsumi (第十七階層都市「ヤマツミ」)
 * The 18th Hierarchical City of Kanayama-Yamabiko (第十八階層都市「カナヤマ-ヤマビコ」)
 * The 19th Hierarchical City of Kanayama-Yamabime (第十九階層都市「カナヤマ-ヤマビメ」)
 * The 20th Hierarchical City of Haniyasu-Yasubiko (第二十階層都市「ハニヤス-ヤスビコ」)
 * The 21st Hierarchical City of Haniyasu-Yasubime (第二十一階層都市「ハニヤス-ヤスビメ」)
 * The 22nd Hierarchical City of Mizuha (第二十二階層都市「ミズハ」)
 * The 23rd Hierarchical City of Wakumusubi (第二十三階層都市「ワクムスビ」)