First Area is located within Japan. It is the location in which the Cauldron that the Black Beast emerged from resides. Within First Area, Shūichirō Ayatsuki's laboratory resides; Kushinada's Lynchpin also resided inside the complex until it's removal.
Originally a lab-like structure deep within the Earth that looked upon the Cauldron inside, District 1 is not only the birthplace of the Black Beast as a result of a failed experiment, but it is also the area in which Shūichirō Ayatsuki was killed and where Relius Clover was consumed and sent many years into the future.
First Area is first explored in BlazBlue: Phase 0 novel. Ragna the Bloodedge, Celica A. Mercury, Nine and Trinity Glassfille believed that Shūichirō Ayatsuki might be residing inside the complex after the birth of the Black Beast; together, they ventured towards the complex and eventually, with the help of Trinity, were able to find Shūichirō's laboratory and the towering Kushinada's Lynchpin. After having an argument over the morality of Celica sacrificing herself to the Lynchpin in order to save the world from the Black Beast, and a brief battle between Nine and the recently arrived Jūbei, the aforementioned monstrous beast arose. After Nine teleported Celica, Trinity and herself out of the lab, Jūbei and Ragna engaged the beast. It is in First Area that Ragna was consumed by the Black Beast in order to delay its movement for a year.
Some time before the Phase Shift series, the Susano'o Unit was excavated in First Area by the Japanese Government and was immediately hidden so the world would not be made aware of its existence.
First Area appears as a massive gaping hole in the ground that appears to be constructed from materials from the 2100's. However, upon closer inspection, there is large evidence of it being made via alchemy and magic instead of being man-made. To traverse to the bottom where Shūichirō's lab and the Cauldron resides, one must access the somewhat 'modern' elevator.
On the bottom floor where the Black Beast was born, the metal sheet covered walls and ceiling are torn asunder with claw marks from the Beast, leaving the exposed earth underneath. Shūichirō's battered equipment litters the place in a tossed aside manner, as if it had all been uprooted from its place. At the end of the hallway lies the Cauldron which birthed the Beast.
A previously covert entrance to Shūichirō's lab resides near the beginning of the hallway. The inside of the lab is described as "very strange". Despite six years of absence in the facility, the electricity was still running, as are some of the machines; even the majority of the documents found there seem to hold the illusion that they were recently printed. At the opposite end of the lab lay Kushinada's Lynchpin, suspended via gigantic metal chains that clung to the adjacent walls.
The facility is said to be extremely well built, with Trinity claiming that there is magic protecting it from external harm so it will last much longer.