In Comics
Green Lantern Vol 2 #59 (March, 1968)
Marvel Graphic Novel #4 - The New Mutants: Renewal
Base
Formerly New York City; currently Oa
(current) X-Factor Investigations, New York City (former)Professor Xaviers School of Gifted Youngsters, Salem Center, Westchester County, New York; Muir Island, Scotland; X-Factor headquarters, Embassy Row, Washington, D.C.; X-Factor Headquarters, New Yo