West Thumb Geyser Basin in Yellowstone National Park is a small yet vibrant geothermal area nestled on the western shore of Yellowstone Lake, the largest high-altitude lake in North America.

Although smaller than other famous geyser basins like Midway Geyser Basin or Black Sand Basin, West Thumb offers stunning scenery and unique features - including hot springs, geysers, mud pots, and fumaroles.

Interestingly, West Thumb is actually a crater within a crater!

About 125,000 years ago, a massive volcanic eruption created the West Thumb Caldera, which sits inside the larger Yellowstone Caldera. This explosion likely reshaped Yellowstone Lake, forming the deep bay we see today.

Why Visit West Thumb Geyser Basin?

West Thumb offers something special that other geyser basins don't—a lakeside view. The geothermal features here sit right on the shores of Yellowstone Lake, blending the vibrant colors of hot springs and geysers with the lake's cool blue waters. Colorful pools, steaming geysers, and a stunning lake backdrop provide the perfect setting for incredible photos.

Moreover, despite its many geothermal wonders, exploring the basin is easy. The boardwalk loop is only 0.8 miles (1.3 km) long, mostly flat, and takes just 30–45 minutes to complete.

Top Things to See at West Thumb Geyser Basin

West Thumb is packed with geothermal wonders. Here are spots you will see along the boardwalk:

Abyss Pool

This is one of the deepest hot springs in Yellowstone, with turquoise and emerald-colored water plunging 53 feet (16m) into the earth.

Black Pool

Despite its name, this spring is now a brilliant blue-green spring. It used to appear black due to the bacteria, but when the water temperature increased in 1991, it killed the bacteria, revealing clear water.

Fishing Cone

Fishing Cone is one of West Thumb's most famous geysers. In the 1800s, visitors would catch a fish in the lake and cook it in the geyser without even taking it off the hook! While this practice is no longer allowed (for safety reasons), the story adds a fun historical twist to the site.

Twin Geyser

This geyser has two vents that can shoot water as high as 75 feet (23m). While not as predictable as Old Faithful, it’s an exciting sight if you catch an eruption.

Thumb Paint Pots

Bubbling mud pots colored by minerals and sulfuric acid break down the surrounding rock. They are especially active after rain.

Lakeshore Geyser

This geyser sits right on the edge of Yellowstone Lake, and depending on the lake's water level, it can be partially submerged.

Percolating Spring

A constantly bubbling spring along the boardwalk is a reminder of the geothermal energy below the surface.

King Geyser

King Geyser eruptions are unpredictable but impressive, releasing large amounts of water and steam when it finally blows.

Blue Bell Pool

This hot spring is vibrant blue in color due to its extreme depth, high temperature, and clear water.

Why Are the Hot Springs So Colorful?

The vibrant colors come from water's temperature and thermophiles, tiny heat-loving organisms that thrive in extreme temperatures.

• Blue and green: These colors appear in the hottest springs where few organisms can survive.
• Yellow, orange, and red: Cooler areas allow different types of bacteria to thrive, creating colorful mats around the springs.

These natural rainbows make for breathtaking photography. Have you ever seen anything like it before?

Wildlife at West Thumb Geyser Basin

While walking the boardwalk, keep your eyes peeled for wildlife. This area is home to:

• Bison: These massive animals often graze nearby. Always stay at least 25 yards away for safety.
• Elk and deer: These graceful creatures are commonly spotted in the surrounding woods.
• Waterfowl and otters: The geothermal heat keeps parts of Yellowstone Lake from freezing in the winter. This creates a perfect fishing spot for otters and birds.

Pro Tip: Visit early morning or late evening for the best chances of seeing wildlife

How to Stay Safe at West Thumb

Here are a few safety tips to keep in mind:

1) Stay on the boardwalk at all times. The ground around geothermal features is thin and can collapse under your weight.

2) Keep children close to you. The water in the springs is scalding hot and can cause severe burns.

3) Follow all posted signs and park regulations. They're there to protect you and the fragile ecosystem.

Tips for Visiting West Thumb Geyser Basin

Here's how to make the most of your visit:

• Time your visit: Mornings and evenings are less crowded and offer the best lighting for photos.
• Pick up a trail guide: For just $1, you can grab a trail guide at the information center to learn more about each feature.
• Use the NPS app: Download the National Park Service app before your trip. It has offline maps and self-guided tours for West Thumb.
• Bring layers: Yellowstone's weather can change quickly, so pack a jacket even in summer.
• Accessibility: The boardwalk is mostly wheelchair accessible. However, some areas on the hill may require assistance.
• Leave pets at home: Pets are not permitted on the boardwalk for their safety and the safety of wildlife.