Yellowstone

The world's first national park spreads across Wyoming, Montana, and Idaho, sitting atop one of Earth's largest volcanic hotspots. Geysers, prismatic hot springs, fumaroles, and churning mud pots punctuate a wilderness that shelters one of North America's largest free-roaming bison herds. Old Faithful erupts on schedule; the Grand Prismatic Spring blazes in rings of cobalt, amber, and jade.