• An aerial view of Old Faithful erupting taken from Observation Point with the Old Faithful Inn to the side.

    Yellowstone

    National Park ID,MT,WY

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  • Construction Work To Result In Yellowstone Road Closures After Labor Day

    Two sections of Yellowstone’s Grand Loop Road will be closed due to construction after the Labor Day holiday weekend. Travel between some points will involve long detours and significantly longer than normal travel times. More »

Mudpots and How They Work

A bubbling mudpot

Bubbling Mudpot

Mudpots are acidic features with a limited water supply. Some microorganisms use hydrogen sulfide, which rises from deep within the earth, as an energy source. They help convert the gas to sulfuric acid, which breaks down rock into clay. Various gases escape through the wet clay mud, causing it to bubble. Mudpot consistency and activity vary with the seasons and precipitation. The sights, sounds, and smells of areas like Artist and Fountain paint pots and Mud Volcano make these curious features some of the most memorable in the park.
 
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Did You Know?

Upper Geyser Basin Hydrothermal Features on a Winter Day.

Yellowstone contains approximately one-half of the world’s hydrothermal features. There are over 10,000 hydrothermal features, including over 300 geysers, in the park.