The gym was built under Raimon Junior High and it was used first by the legendary team, Inazuma Eleven. In the gym, Raimon evolved their individual strength and learned a lot of techniques. The training center is totally isolated and the door is locked by a timer set on 9999 seconds, which is equivalent to a training session.
The training is divided into six courses (in the game):
- Attack Course
- Defence Course
- Speed Course
- Technique Course
- Strength Course
- Special Course (Game only)
- In the game, the training center's entrance was built under the school's first Governor's statue. In the anime, the entrance above ground was the Inaccessible Door, the first of the seven wonders of Raimon Jr. High.
- One of the rumors which is about one student who entered the door never returned was actually a misunderstanding about the training center's Training Session.