The trail through Back Basin is a 1½-mi loop guiding you past Steamboat Geyser. When it erupts fully (most recently in 1985), it's the world's largest, climbing 400 feet above the basin. More often, Steamboat growls and spits constantly, sending clouds of steam high above the basin. Kids will love the Puff 'n' Stuff Geyser and the mysterious cave-like Green Dragon Spring. Ask trangers for an anticipated schedule of geyser eruptions—you might catch the Echinus Geyser,
which erupts almost hourly.
Grand Loop Rd. at Norris, Yellowstone National Park, Wyoming, USA