The Magical Inquisition travels the country in search for children with magical potential. When they’re found they’re being deported to the academy, no exceptions allowed.
The complex itself resides on a large plateau enclosed by a magical barrier. In ancient history it was the home of one of the Orinas, the former rulers of Orion, but after The Great War it has been put to service the crown. A part of the complex resides within the mountain, but is mostly inaccessible, unless you’re a direct descendant from the Orinas.
New arrivals all go through an initiation rite marking them with a magical seal, making them unable to cross the barrier. This makes it a prison and a safe haven for magicians.
They have an autonomous government, consisting of seven counselors and the head of office. Those eight people are responsible for everything regarding the institution and acquiring.
I’ve made a crude map of the place so I can make consistent descriptions of routes the characters walk. The starlike figure is the main building with some greenhouses added to it. On the bottom left are the living quarters for all student who have come at age and are allowed to live on their own. Sort of like a dorm, with an inner garden.
The grey starlike shape is the main square with all the little shops, the entrance to the library and the amfitheater just north from there. Along that path are also the seven houses for the counselors In the bottom there’s the gate with guard houses, a warehouse and other facilities to run the daily activities.
North from the main building is a lake, some woods and the entrance to the inner parts of the complex, which go deep in to the mountain.