The northernmost developed area at Yellowstone revolves around the one-of-a-kind travertine terrace features here—one of the planet’s best examples of this type of geologic sculpture. Though they’re fueled by the same potent combination of heat, geology, and water that power the rest of the park’s thermal features, Mammoth’s terraces are unlike anything else you’ll see here.
Mammoth’s signature feature looks like a series of stair steps frosted with a chalky white trimming. Bright greens, oranges, and yellows cover some of the terraces, and intricate ripples of rock glaze others. Steaming pools rise in some areas, and others resemble dry, bare, white fields. In this area, limestone deposited by an ancient sea is common. As in other thermal areas, an underground heat source causes groundwater to rise back to the surface; as it does, the water dissolves the calcium carbonate in the limestone. Once on the surface, the water quickly deposits the mineral to build the terraces at the pace of a ton of limestone every 24 hours. Heat-loving microorganisms called thermophiles create the color swatches in some areas.
This is one of Yellowstone’s most dynamic zones. Old hot springs may go dry for days, weeks, or much longer, leaving bare expanses. New springs perpetually seep up in different places, sculpting fresh terraces. Such constant shifting makes Mammoth an especially fascinating stop: Where else can you watch geologic changes practically before your eyes?
A series of interconnected boardwalks, some of which are wheelchair accessible, wind through the active terraces, granting an up-close look. Start with the Lower Terraces ★★, where the boardwalk connects you to major features and then climbs 300 feet to an observation deck up top. Walking the whole thing out and back covers about 1.5 miles.
Liberty Cap greets you near the start of the trail: This 37-foot, pointy pillar formed when a high-pressure hot spring steadily deposited minerals over hundreds of years. Next up is Palette Spring, a gorgeously furrowed slope painted in broad strokes of orange and brown. Minerva and Cleopatra Terraces are just beyond. This area changes frequently from active to dry. Jupiter and Mound Terraces are similarly volatile: Mound has cycled through on-and-off periods for decades, and Jupiter flowed so forcefully in the 1980s that it overtopped the boardwalks a few times. Hoof it up the final staircases to the overlook, where you’ll get a top-down view of the terraces and several hot springs.
From here, you can connect to Upper Terrace Drive to walk the 1.5-mile loop through more terraces (alternatively, hop back in the car and drive it). Though there’s a collection of live and dormant terraces and several nice views from up here, particularly around Canary Spring, this loop is skippable unless you’re a real terrace fiend.
Back in the main Mammoth Hot Springs area, consider taking the short, self-guided Fort Yellowstone tour (from the Albright Visitor Center). In Yellowstone’s early days, before there was a National Park Service, the U.S. Army played the role of protectors of the park’s wildlife and resources. Many structures from that era (1886–1916) still stand; check out officers’ quarters, a chapel, cavalry barracks, and more (although you can’t enter most buildings).
Just steps from the lower terrace is the trailhead for the Beaver Ponds Loop Trail, a 5-mile jaunt through fir and spruce, then sagebrush and aspen, along a trail that follows Clematis Gulch. The ponds are about 2.5 miles from the trailhead, where the toothy beavers are most active in early morning and at night. The area is also a hangout for elk and bears, and can be closed early in the summer season.
Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.