Adjacent to Mammoth Hot Springs Hotel and Visitor Center, five miles (8 km) from north entrance, on the northwest side of the upper loop drive.
The Terraces, one of Yellowstone's fastest-changing hydrothermal areas, are one of the world's few active travertine (limestone) terraces. Building for thousands of years, the terraces at Yellowstone are still growing and their hot springs can deposit up to two tons of travertine daily.
Cautions Mammoth Hot Springs Terraces, Yellowstone
- Stay on boardwalks and walkways. The water can be boiling temperature or higher, what looks like solid ground may be only a thin crust, and going off the trails damages fragile plants and rock formations.
- Don't throw anything into the pools. Even a small object like a coin can choke off the water flow and kill an active formation.
- Pets are not allowed on the boardwalks.
Mammoth Hot Springs Terraces Yellowstone Sights
Water flow patterns change often here. We visited in 2001, and when we returned in 2003, we found new pools forming and old ones dried up.Start at the upper or lower parking lot, or walk from the hotel and Visitor Center. Pick up a trail guide to better understand what you see. The guide includes a map and background information. Use it and return it for free, or the National Park Service requests a 50-cent donation if you take it with you.
You may find things different than described here, but the biggest, most active formations at Mammoth Hot Springs Terraces, Yellowstone, include:
- Opal Terrace: Across the road from main trails, and threatening a historic house, this formation started growing up to a one foot per year in the 1920s.
- Liberty Cap: Created by a spring that stayed active and in one location for a long time, this 2,500-year-old, 37-foot-tall (11 m) feature now stands dormant.
- Palette Spring: Named because it resembles the effect an artist might achieve by letting watercolors run down a vertical surface, the spring displays a range of orange and brown colors.
- Minerva Terrace: This giant layer cake shape, named for the Roman goddess of artists and sculptors, started forming in the 1990s, and dried up in 2002.
- Jupiter and Mound Terraces: Once the area's most beautifully-colored spring, Mound Terrace has been inactive in recent decades. Jupiter Terrace overtook the boardwalk several times in the 1980s, but then dried up in 1992.
- Main Terrace: This large terrace is near the upper parking lot, and can be seen from the boardwalk at New Blue Spring. Its flow starts and stops several times a year. On Main Terrace are Canary Spring (named for its yellow water) and Cupid Spring, active until early 2000.
- Views: From the top of the terraces, Yellowstone views include the springs, with Fort Yellowstone and the hotel below.
How Mammoth Hot Springs Terraces, Yellowstone, Got There
Rain and melted snow seep underground. A magma chamber left behind after a volcanic eruption 640,000 years ago heats the water.While most Yellowstone hydrothermal features are made from the mineral rhyolite, Mammoth Hot Springs' formations are limestone, deposited by an ancient sea.
Hot underground water contains a weak acid that dissolves the limestone and carries it to the surface through cracks. Limestone redeposits at the surface, forming rock as fast as one foot per year.
As if all this weren't enough, nature adds color to the wedding-cake-white stone layers. Heat-loving organisms called thermophiles, colorless and yellow in the hottest water and orange brown and green in cooler pools, tint the landscape like a watercolor painting.
