Basement — The lowest floor of a building, below ground level.
Mount Aso
A mysterious underground chamber has been discovered on the grounds of Mikazuki Castle.
It measures 6 square meters and is approximately 3.2 meters deep. There are two staircases leading in and out.
While it has been determined that the chamber was located beneath the residence of a senior retainer named Seibei Sagara, its purpose and function remain unknown.
Various theories have been proposed—including that it served as a water reservoir, a well, a bathhouse, a facility related to Christianity, or a Jewish ritual bathing facility—but none of these has been definitively confirmed.
Incarnation of the Basement