Mud Volcano - Yellowstone National Park {Video}

Mud Volcano trail is the perfect place to explore some of Yellowstone National Parks hydrothermal features.

This area of thermal features includes the Mud Volcano, Mud Geyers, Dragon's Mouth Spring, Grizzly Fumarole, Sour Lake, and Sizzling Basin to just name a few. 

Here are my top finds for Canyon & Grant Areas of Yellowstone NP
🏨Lodges: Canyon Lodge, Grant Village, Lake Yellowstone Hotel
📍Tours: Yellowstone Lake Morning Kayak Tour with Lunch, Grand Canyon of the Yellowstone Loop Hike with Lunch
🐻 Save time! Buy your National Park Pass before your trip

Mud Volcano - Yellowstone National Park

Trail Distance - .6 mile

When visiting the Mud Volcano Trail you will want to be prepared for the strong odor of rotten eggs which is caused by hydrogen sulfite gas.

This area has many faults that converge here so earthquakes are common. It is near the greatest uplift and sinking of the Yellowstone Caldera floor.

This guide follows the trail in a clockwise route which is less steep than the counter-clockwise route. 

Dragon's Mouth Spring

When you walk up to Dragon's Mouth Spring it feels like the cave is belching steam and having a rough day. LOL! Over the past 24+ years, the spring has seen some big changes.

In 1994 the surging action decreased and then in 1999, the water temperature dropped ten degrees and the color changes from green to chalky white. 

Dragon's Mouth Spring has also been called Gothic Grotto, Blowing Cavern, and the Belcher. 

Mud Volcano

Mud Volcano reminds me of Halloween and a gurgling witches cauldron of mud.  The muddy water is constantly undercutting the back wall.

When early explorers to Yellowstone encountered the Mud Volcano they said it was terrifying. At that point, it was a volcano-cone like structure 30 feet high and 30 feet wide that erupted mud tall enough to cover trees.

In 1870, when Nathaniel P. Langford visited he said it was more of a bubbling mass of mud which made them believe violent eruptions must have blown out the volcano cone. 

At this point on the trail, it does go up a short distance via either stairs or steeply graded pavement and boardwalk. 

From here you can continue along the trail or turn around and follow the trail back down to the parking lot.

Grizzly Fumarole

Grizzly Fumarole changes based on the weather. If you visit during a time when it has been raining you will find a large watered-down mudpot with a series of smaller and thicker mudpots or fumaroles.

During the dry season when there is little to no rain you may be surprised to find an area with hot water hissing far below and the pools looking almost empty.

 

Sour Lake

Sour Lake is a large pool of water that looks like you want to dive right into it and cool off. 

Please do not touch this water!

The water is so acidic it would burn your skin like battery acid! The pools acid comes from microorganisms that create sulfuric acid as they consume sulfur.

The microorganism is what creates the color of the lake.

 

Black Dragon's Caldron

Black Dragon's Caldron is a relatively new destination along the Mud Volcano Trail. It appeared in 1948 when it appeared along a crack in the earth.

Since 1948 this feature has moved 200 feet south along the crack in the earth.

The caldron was named by a park ranger for the color and the apparent lashing o the "dragon's tongue".

 

Churning Caldron

Churning Caldron has had some major changes since earthquake activity in 1978-79. The pool was a cool spring covered in colorful mats of microorganisms.

After the earthquake activity, the water was superheated which killed off some of the mat-forming microbes.

Starting in 1996 the caldron started throwing water 3-5 feet high and now averages a temperature of 164 degrees Fahrenheit.

 

Sizzling Basin

The sizzling basin has also undergone changes form the 1960s to the 1970s.

In the 1960s the Sizzling Basin was similar to a hot grease-filled frying pan.  During the 1970s, the pool cooled and lost part of its carbon dioxide supply which allowed microorganisms to grown and create a lush mat that covered most of the surface.

When earthquakes struck in 1978-79 the pool was again super-heated killing off the microorganisms.

 

Mud Geyser

One thing that is constant in this area of Yellowstone is changed. These features change daily, weekly, monthly, and yearly so it is worth revisiting to see what changes have happened.

Mud Geyser was described as a boiling spring, placid pod, deep dry funnel or an active geyser by the Washburn Expedition in 1970.

At that time the geyser would explode muddy water 500 feet into the air every few hours.

By the 20th Century, the geyser had died due to its plumming getting clogged with mud and rocks.

Soil temperatures skyrocketed ni 1993 for unknown reasons causing trees to start dying around the geyser's south rim.

A new feature burst onto the scene in January 1995 on the south bank of Mud Geyser. All of a sudden steam vents and shallow pools sizzled. 

By 1999 mud pots formed and then exploded creating a deep hole with even more sizzling features and mud. 

 

Mud Caldron

The bubbling in Mud Caldron is caused by carbon dioxide and other gases rising from several thousand feet below. 

Sulphur Caldron

Sulphur Caldron is located across the Grand Loop Road from Mud Volcano. 

Sulphur Caldron is one of the most acidic springs in Yellowstone. These waters have a pH of approximately 1-2 which is equivalent to car battery acid or stomach fluids.

Where is the Mud Volcano?

Mud Volcano is located between Canyon Village and Fishing Bridge.

You will drive right by Mud Volcano on the Grand Loop Road when driving towards Hayden Valley from Lake Yellowstone. 

Best Yellowstone National Park Tours & Activities

Yellowstone Lake Morning Kayak Tour with Lunch
⭐️ Rating: 4.9 out of 5 Stars (206+ reviews) | ⏳ Tour Length: 4 hours | 🛶🌋 Check Rates and Availability

This morning kayak tour is one of the most unique ways to experience Yellowstone, Guests will paddle on Yellowstone Lake for approximately 6 miles along the shore of the West Thumb. Geysers and hot springs visible only from the water are a highlight, along with frequent wildlife sightings including elk, waterfowl, bears, and bald eagles along the shoreline. A full brown bag lunch with sandwich, fruit, chips, and snacks is included, along with hot coffee or tea, a kayak, paddle, life vest, paddle jacket, and dry bag. Suitable for first-time kayakers and experienced paddlers alike.

Grand Canyon of the Yellowstone Rim and Loop Hike with Lunch
⭐️ Rating: 4.8 out of 5 Stars (407+ reviews) | ⏳ Tour Length: 6 hours | 🥾🏔️ Check Rates and Availability

This guided loop hike is one of the most spectacular half-day experiences in the park and a favorite that many visitors call the highlight of their entire trip. Unlike the Lamar Valley hike, this one focuses on Yellowstone's dramatic canyon country, hugging the rim of the Grand Canyon of the Yellowstone River with jaw-dropping views of the Upper and Lower Falls before looping through forest trails to hidden lakes, mud pots, and steam vents that most visitors never find on their own. A packed lunch is included, along with bear spray and binoculars.

Self-Guided Audio Driving Tour in Yellowstone and Grand Teton
⭐️ Rating: 4.7 out of 5 Stars (67+ reviews) | ⏳ Tour Length: 8 hours to 1 day (self-paced) | 🚗 Check Rates and Availability

This GPS-triggered audio driving tour covers both Yellowstone and Grand Teton National Parks in a single purchase, making it one of the best values available for road trippers exploring the Greater Yellowstone ecosystem. Powered by GuideAlong, the narration fires automatically as you reach each stop, covering Old Faithful, Grand Prismatic Spring, Lamar Valley, Mammoth Hot Springs, the Grand Canyon of the Yellowstone, Jenny Lake, Mormon Row, and more, with 550-plus points of interest across both parks. Works fully offline once downloaded, so no cell service is needed anywhere in the park. One purchase covers everyone in the vehicle with no expiry, and you can start, stop, and resume any time across multiple days. Reviewers consistently say they would have missed major sights without it.

Click here to find more great Yellowstone National Park Tours.

Attractions Near Mud Volcano

🚗 Combine a Mud Volcano visit with a drive through adjacent Hayden Valley for a full experience of Yellowstone's central thermal and wildlife corridor
🦅 Watch for bald eagles and ospreys hunting the nearby Yellowstone River just steps from the thermal area
🏛️ Stop at the nearby Fishing Bridge Visitor Center for exhibits on Yellowstone Lake's ecology and the park's thermal geology
💧 Drive north to the Grand Canyon of the Yellowstone, about 10 miles away, where the Yellowstone River drops 308 feet over the Lower Falls into a vivid yellow and orange canyon that inspired the park's name
🌊 Head south to West Thumb Geyser Basin, about 17 miles away on the shore of Yellowstone Lake, where hot springs and geysers bubble and steam directly at the water's edge in one of the park's most uniquely scenic thermal areas
🌊 Visit LeHardy Rapids, where the Yellowstone River rushes over a rocky stretch and native cutthroat trout can be seen jumping during their summer spawning run

Closest Campground 

• Canyon Campground
• Bridge Bay Campground
• Fishing Bridge RV Park

Check out all of the Yellowstone Campgrounds to help plan your time in the park. 

Closest Visitor Center

• Fishing Bridge Visitor Center
• Canyon Village Visitor Education Center

Yellowstone National Park Entrance Fee

New in 2026: Each Non-US Resident aged 16 and older visiting Yellowstone National Park must pay a $100 nonresident fee (in addition to the standard entrance fee), unless admitted with an annual or America the Beautiful Pass. This includes nonresidents entering as part of a commercial tour group, commercial use authorization (CUA) group, or concessioner tour group.

Park entrance fees are separate from camping and lodging fees.

Park Entrance Pass - $35.00 Per private vehicle (valid for 1-7 days from the date of purchase)

Park Entrance Pass - Motorcycle - $30.00 Per motorcycle (valid for 1-7 days from the date of purchase)

Park Entrance Pass - Snowmobile - $30.00 Entry for one driver and one passenger (valid for 1-7 days from the date of purchase)

Per-Person Entrance Pass - $20.00 Visitors 16 years or older who enter on foot, bicycle, or as part of an organized group not involved in a commercial tour.

Annual Park Entrance Pass - $70.00, Admits pass holder and all passengers in a non-commercial vehicle. Valid for one year from the month of purchase.

$20.00 for Non-Commercial Group (16+ persons)

$20.00 for Commercial Sedan with 1-6 seats and non-commercial groups (16+ persons) ($25.00 plus $20.00 per person)

$125.00 for Commercial Van with 7-15 seats

$200.00 for Commercial Mini-Bus with 16-25 seats

$300.00 for Commercial Motor Coach with 26+ seats

Learn more about National Park Passes for parks that have an entrance fee.

$80.00 - For the America the Beautiful/National Park Pass. The pass covers entrance fees to all US National Park Sites and over 2,000 Federal Recreation Fee Sites for an entire year and covers everyone in the car for per-vehicle sites and up to 4 adults for per-person sites.

Buy your pass at this link, and REI will donate 10% of pass proceeds to the National Forest Foundation, National Park Foundation, and the U.S. Endowment for Forestry & Communities.

National Park Free Entrance Days  -Mark your calendars with the free entrance days the National Park Service offers for US citizens and residents.

Additional Yellowstone Resources

Additional Yellowstone National Park Information

• Yellowstone National Park Guide - Your complete guide to exploring the world's first National Park!
• Things to do in Yellowstone - These are the top things to do that you don't want to miss, including exploring the Mammoth Hot Springs, the Museum of the National Park Ranger, Yellowstone Waterfalls, Kayaking in Yellowstone, fishing in Yellowstone, Fairy Falls Trail, and more!
• Yellowstone National Park Facts - Learn more about our 1st National Park and fun facts about the wildlife in the park.
• Yellowstone Wildlife Guide- Complete Guide to seeing wildlife in Yellowstone National Park, including the most popular wildlife viewing areas, including Lamar Valley and Hayden Valley.
• Ultimate Yellowstone National Park Lodging Guide - This complete guide to all of Yellowstone National Park's Lodges and cabins
• Ultimate Yellowstone Camping Guide - This complete guide to camping in Yellowstone includes all front country campgrounds

Yellowstone Geyser Basin Areas 

• Upper Geyser Basin, including Biscuit Basin, Black Sand Basin, and Old Faithful Geyser.
• Midway Geyser Basin, including Grand Prismatic Spring and Firehole Lake Drive.
• Lower Geyser Basin, including Fountain Paint Pot Trail and  Firehole Canyon Drive
• Norris Geyser Basin-This basin is known for having some of the hottest water and springs in the park. It is actually two basins: Porcelain Basin and Black Basin, with famous geysers, including Ledge Geyser, Cistern Geyser, and Steamboat Geyser.
• West Thumb Geyser Basin - Beautiful boardwalk trail with hydrothermal features right next to Lake Yellowstone!
• Mud Volcano - The Mud Volcano area is Located south of Canyon Village and North of Lake Yellowstone. It has several hydrothermal features, including a mud volcano and Dragon's Mouth Spring.

Additional Montana National Parks 

• Complete Guide to Grand Teton National Park - Your complete guide to go explore Grand Teton National Park before or after you visit Yellowstone!
• Epic Guide to Glacier National Park - Complete guide to exploring Glacier National Park
• Little Bighorn Battlefield - Also known as Custer's Last Stand, a place where the Plains Tribes fought their last major battle and won.
• Big Hole National Battlefield - site of the pivotal battle in the Nez Perce War of 1877 between Colonel Gibbon's troops and five bands of the Nez Perce Indians led by the famous Native American Leader, Cheif Joseph.
• Grant Kohr's Ranch National Historic Site - See what ranch life was like in the 1800s in Montana

Check out all of the Montana National Parks along with neighboring National Parks in Wyoming, National Parks in South Dakota, North Dakota National Parks, and Idaho National Parks.

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