Roaring Mountain

Yellowstone National Park: Along the road from Mammoth Hot Springs to Norris Junction is Roaring Mountain. It wasn't roaring when I visited, but you can see several steam vents in the side of the mountain. One way to spot geothermal areas in the park is to look for bleached soil. The heat in the ground, as well as the sulfur, can bleach the soil and kill all the trees in the area.