Ground Floor
A large tiled courtyard leads to the main entrance of the Mansion.

A large, plush foyer splinters off into various rooms, and straight through the foyer leads to the hyperlift, an elevator that leads to the Restricted Access Sub-Levels and the Administration Wing where the offices of the Student Dean, Headmaster, and Administrator are located.

Access to the back is gained through various points, the main entrance being the kitchen. Located at the rear of the estate is an Olympic-sized swimming pool, basketball court and main entrance to Breakstone Lake. Each of these facilities are for students, faculty and X-Men.

The exit and entry point for the X-Men's aircraft, the Blackbird, is beneath the basketball court. Upon departure and landing, a klaxxon will sound warning for anyone nearby to vacate the area. Students are advised to move immediately once the klaxon sounds.

Located behind the large maze is the Girl's Dorm Building, and located behind the 'center tower' of the Mansion is the Boy's Dorm Building.

Classrooms, canteen, and library are all located in the "center tower" of the mansion.

Scattered throughout the ground floor are various rooms and halls, such as a large ballroom that occupies the domed structure near the rear of the building, the students' recreation room, and various other game and computer rooms.

Also located on the ground floor is the nurse's office, which is a ground-level medical lab which anyone can access. It is run by either the medical staff of Xavier's, or RALPH, the holographic doctor.

Forests, farmland, and lakefront surround and isolate the entire estate for miles. The nearest town is Salem Center.

First Floor
This floor is dedicated mainly to the quarters of faculty, staff and X-Men. Aside from the quarters, there are laundry facilities, a workshop, and a recreation area that is strictly for faculty, staff and X-Men.

The Attic
Adorning the top of the mansion is a large glass-paneled dome. Because Storm prefers this spacious attic room it has been adapted to her use. It is filled with various types of plants, much like a greenhouse.

Sub-Levels
In addition to the campus grounds, the Xavier Institute also houses an array of restricted access Sub-Levels. In the sub-levels you will find The Danger Room, War Room, Hangar Bay, holding cells, research and development labs, medical labs and Cerebro chamber.

Voice-activated hallway icons give interactive directions through the sub-levels, though these are restricted to the sub-levels.

Access to the sub-levels is only available to faculty, X-Men, and students -- although students are only granted access once they have spoken to their squad leader or faculty advisor.

To access the sub-levels you must go to the hyperlift at the end of the hallway in the foyer, then proceed through the various security measures such as hand scans, retina scans, voice scans and passcodes.

The Danger Room
The Danger Room consists of two parts, the Danger Room itself, and the Control Room which is housed above the Danger Room. To the untrained eye, the Danger Room is a featureless room. To those who are (un)fortunate enough to engage its systems, it is the ultimate battle simulator. It employs highly advanced technologies from sources such as Forge and Beast.

The Danger Room pits its opponents against an array of physical and holographic opponents that tests a trainees' mastery over their mutant powers to peak endurance.

Using the advanced technologies, the Danger Room can give the illusion of being many times bigger than it actually is. Anything from gravity, heat, humidity, or texture can be manipulated from the control booth.

Students are not permitted to be in the Danger Room unless accompanied by an instructor or X-Man.

Dormitories
The first, second and third floors are for high school level students currently. Each room has a half bath (toilet and sink), while there is one bathroom with shower stalls, vanities, and toilets on each floor. While each bedroom is large enough for two students, the school has yet to have enough students to have to double up. Students may, of course, ask to share a room. Each room may be decorated to the student's taste. A laundry room is set up on each floor, as well as a rec room. The rec room contains a pool table, foosball table, ping pong table, big screen TV with a Blu-Ray and DVD player, as well as the latest video game systems. There is a kitchenette with snack food.

Information found here.