Yellowstone National Park

Yellowstone National Park is an area of heavy volcano activity, located in the state of Wyoming in the United States of America.

Transformers Legends anthology
During their hunt for Mini-Cons, the Autobots and Decepticons had a confrontation at Yellowstone, sparking fears amongst the humans that their battle would aggravate the geothermal activity at the site. Though the Decepticons pressed their attack, despite warnings, the great Autobot Riptide arrived, having been warned of the danger by a human radio show. He and the human Jake Williams helped fight Megatron, and the Decepticons soon fled from Yellowstone, allowing the Autobots to retrieve the Mini-Con they had been searching for. Optimus promised that they would fish Jake's truck, Nelly Belle, out of the mud pit it had fallen into during the battle, and help restore it to working order.