Research Facility A

Research Facility A was a secret military facility in the Yokohama Settlement in Japan, which researched artificial abilities. After the facility and its surrounding area were destroyed eight years prior to the Arahabaki Incident, the explosion's aftermath became Suribachi City, named after its mortar shape like that of a .

Description
The facility was located on the borders of the Yokohama Settlement. During its operation, armed soldiers guarded it outside, who prevented even children from intruding it by killing them. It was also built with more or less 15 sealable doors.

It also housed a wide, ceiling-high cylinder where they kept Chūya Nakahara as their test subject for Project Arahabaki, which was filled with a bluish-black liquid that made its glass surface seem opaque when viewed from outside.

Background
Towards the end of the Great War, experiments were performed in Research Facility A on how to create artificial abilities using knowledge they acquired from a French researcher's studies. In so doing, they conducted research on Chūya, on whom they were able to successfully replicate the research's outcome and seal a singularity which they named Arahabaki.

France soon caught wind of a high-energy being that Japan was researching and sent two operatives, Arthur Rimbaud and Paul Verlaine, to obtain it. In a chaos that broke out as a result of the pursuit on the intruders and the latter two's internal dispute, Rimbaud attempted to absorb Arahabaki. However, he instead unwittingly absorbed the seal containing the life-form, causing it to unleash black flames and decimate the facility and everything within one mile in a massive explosion.

Before long, people arrived in the wasteland left by the blast's aftermath, and they began to build their own city, eventually becoming Suribachi City. A second facility, Research Facility B, was also built later on and modeled after the facility, where researchers continued their study on artificial abilities in secret.