Norris Geyser Basin
This basin is one of the most remarkable - it is home to Steamboat Geyser which shoots 328 feet into the air. There are plenty of other land and water formations here such as giant craters. One such crater was formed as recently as 1989 when an explosive hydrothermal event shot out rocks, boulders, and plenty of boiling water. The park is open 24/7 during the spring and summer (closed in fall and winter) with no parking fees. See the website for updates on openings and closures.