The primary Yellowstone caldera was created by one volcanic eruption, while West Thumb came about as the result of another, later volcanic eruption. This unique geyser basin is the only place to see active geothermal features in Yellowstone Lake. Two boardwalk loops are offered; take the longer one to see features like Fishing Cone, where fishermen used to drop their freshly caught fish straight into boiling water without ever taking it off the hook. This area is particularly
popular for winter visitors, who take advantage of the nearby warming hut and a stroll around the geyser basin before continuing their trip via snow coach or snowmobile.
Grand Loop Rd., 22 mi north of South Entrance, Yellowstone National Park, Wyoming, United States