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Hidden under the Yamigakure Administrative building is the secret Anbu Forces base. While it is located just under the building, you cannot access it by the administrative building itself. Instead, various shops and businesses have secret entrances in and around them to lead to this place. On top of that is a seal that only those with the Yamigakure seal can pass through.
This place is underground and is rather small, but is highly durable. Inside are various hidden rooms that hold weapons and other items. The base itself is no larger than a house bound to a single floor.
