Thumb Geyser

West Thumb Geyser Basin sits on the western shore of Yellowstone Lake in Yellowstone National Park. Its boardwalk loops past colorful hot springs and steaming thermal features close to the water, with lake and mountain views along the way. The level route includes some inclines and declines, and the basin is a convenient short stop for seeing geothermal activity at the lakeshore. Look for the bright bacterial mats around the pools, and take time to watch the changing steam and water. Restrooms and picnic spots are available.

Thermal pools beside the lake

West Thumb Geyser Basin lies on the western shore of Yellowstone Lake. Here, geothermal features sit close to the water’s edge, giving the walk a different setting from basins farther inland. The contrast between the deep blue lake and the colored mats around the hot springs is one of the area’s defining sights.

The basin is part of Yellowstone’s thermal areas. West Thumb Lake itself formed within the larger Yellowstone caldera, creating a caldera within a caldera. Early 19th-century explorers wrote about this part of the park, and the basin later became a stop on stagecoach journeys from the Old Faithful area. Travelers could continue by stagecoach or take a steamship across the lake toward the Lake Hotel.

Following the boardwalk

A maintained boardwalk leads visitors around the thermal features. The route is an easy walk, with some inclines and declines but no steps. Pools, vents and the shoreline remain close to the path, so take care to stay on the boardwalk as you look at the features.

The steam can obscure views at times, and parking can fill up. An early start or a visit outside peak periods can make parking easier. Restrooms and picnic spots are available in the area. If you want to extend the day, nearby options include the Elephant Back Mountain Trail and Storm Point Loop.