Yellowstone National Park is a national park in the northern Mountain States, mostly in Wyoming but extending into Montana and Idaho.
T.O. Morrow had a hideout in Teton County, 100 meters below the Old Faithful geyser. There, he repaired his androids Red Tornado, Red Inferno and Red Torpedo, and created their more powerful brother, Red Volcano.
Volcano went renegade, and planned to use Yellowstone's giant dormant super-volcano to wipe out all of humanity. After the Team failed to stop him, Volcano's siblings sacrificed themselves to bring down Volcano. Red Tornado survived, but lost his legs.