Norris Geyser Basin

Back Basin Loop -- This level boardwalk is easily negotiable in an hour and passes by Steamboat Geyser, which has been known to produce the world's highest eruptions. How often? About once a decade, with an impressive spurt of activity from 2000 to mid-2005: six eruptions -- and counting. Wait instead by Echinus Geyser because its colorful pool fills and erupts several times a day.

1.5 miles round-trip. Easy. Access: Trail head is located at Norris Geyser Basin.

Porcelain Basin Trail -- You'll share this boardwalk with other folks, but it takes you across a broad, flat basin where steaming water makes colorful trails. You can complete the walk in less than an hour, but you'll probably stop to look closely at some of these geothermal features, a few of which periodically spit and rumble in small eruptions.

.5 mile round-trip. Easy. Access: Trail head is located at Norris Geyser Basin.