Graymalkin Industries was a structure that was built in San Francisco at Marin Headlands where it was palced at long abandoned military bunkers that lined the cliffs overlooking the Pacific Ocean. Construction was authorised by mayor Sadie Sinclair and was the undercover name for the X-Men's new headquarters in the region after their departure from the X-Mansion which had been previously destroyed in an earlier battle. Intended to fulfil many of the elements of the X-Mansion, such as containing the bulk of its facilities underground which included the Danger Room, the Cerebra chamber and a hanger bay for the Blackbird. It was not only home of the empowered Mutants but also the depowered ones as well.