The Forest was used as a camp for both the Brotherhood and the large contingent of Omegas that joined in alliance with them. In an unspecified area of the perimeter was a hatch that led down to Magneto's underground sanctuary. Similar to his private quarters on Genosha, the sparsely furnished room contained only a desk while the walls were lined with an unidentified metal.
It was infiltrated by Wolverine in order to find Jean Grey and take her back to the X-Mansion. However, before Wolverine could even speak to her, Magneto caught him and magnetically hurdled him away through the tree branches.