The X-Mansion's address is 1407 Graymalkin Lane, Salem Center, located in Westchester County, New York. The school's motto is "mutatis mutandis." In a recent edition of the comic, Wolverine re-opened the school, at the same address, under the name of the Jean Grey School for Higher Learning. After it was discovered that the Terrigen Cloud had become toxic to mutants enough to have them die from M-Pox, Storm had the mansion moved to Limbo and renamed it X-Haven to keep mutants safe from the Terrigen until a cure could be discovered. After Medusa destroys the Terrigen Cloud so the mutants could survive Kitty Pryde moves the mansion from Limbo to Central Park, New York and renames it The Xavier Institute for Mutant Education and Outreach.
The X-Mansion is the inherited property of Charles Xavier (Professor X) and has been in the Xavier family for ten generations including two known mutants in the lineage, both becoming detached from the family. Little else is known about them or their mutations.
As Xavier's School for Gifted Youngsters, the X-Mansion was the training site of the first two generations of teenage X-Men:
In X-Men vol. 2 #38 (November 1994), the X-Mansion was renamed from Xavier's School for Gifted Youngsters to the Xavier Institute for Higher Learning, as most of the X-Men were adults rather than teenagers by this time. Xavier's School for Gifted Youngsters was relocated to the Massachusetts Academy in Western Massachusetts (a Marvel created town or region called Snow Valley somewhere in The Berkshires), which served as the training site of the third generation of teenage X-Men beginning in Generation X #1 (November 1994).
The Massachusetts Academy closes permanently in Generation X #75 (June 2001). Shortly thereafter, the school for young mutants is reopened at the X-Mansion, but the name remains "The Xavier Institute for Higher Learning" despite the younger student body. The fourth generation of mutant teenagers, featured in Grant Morrison's New X-Men (2001–2004) and in New Mutants (2003–2004; relaunched as New X-Men: Academy X, July 2004–February 2008), study at the mansion until it is destroyed during the 2007–2008 story "Messiah Complex" and the X-Men subsequently disband and close the Institute.