
A collection of mudpots.
Mudpots
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 to wet clay mud and creates the area’s smell. The pungent odor of rotten eggs is caused by the hydrogen sulfide gas.
Various gases escape through the wet clay mud, causing it to bubble. Mudpot consistency and activity vary with the seasons and precipitation.
Use Caution in Hydrothermal Areas
- Stay on boardwalks and designated trails.
- Hydrothermal water can severely burn you.
- Never run, push, or shove.
- Supervise children at all times.
- Do not scratch hydrothermal mats.
You are responsible for your safety.
Think safety, act safely. Yellowstone is a dangerous place.
Is there something we missed for this itinerary?
Itineraries across USA

Acadia

Arches National Park

Badlands

Big Bend

Biscayne

Black Canyon Of The Gunnison

Bryce Canyon

Canyonlands

Capitol Reef

Carlsbad Caverns

Channel Islands

Congaree

Crater Lake

Cuyahoga Valley

Death Valley

Dry Tortugas

Everglades

Gateway Arch

Glacier

Grand Canyon

Grand Teton

Great Basin

Great Smoky Mountains

Guadalupe Mountains

Haleakalā

Hawaiʻi Volcanoes

Hot Springs

Indiana Dunes

Isle Royale

Joshua Tree

Kenai Fjords

Kobuk Valley

Lassen Volcanic

Mammoth Cave

Mesa Verde

Mount Rainier

North Cascades

Olympic

Petrified Forest

Pinnacles

Rocky Mountain

Saguaro

Shenandoah

Theodore Roosevelt

Virgin Islands

Voyageurs

White Sands

Wind Cave

Yellowstone

Yosemite

Zion