Out of This World: Mammoth Hot Springs

[Leslie Griffin is an editor living in New York City, where nature is hard to come by. She travels to national parks and other hiking destinations whenever the opportunity arises.]

Jupiter Terrace

Of the many wondrous things I saw on a recent trip to Yellowstone National Park, Mammoth Hot Springs is the one I believe will stick with me the longest simply because it’s so unlike anything I’ve ever seen or am likely to see in years to come.

If the name leads you to believe this site is a hot spring that one visits to take a “cure,” you’re not alone. That’s what I thought it was before visiting. I had some vague notion that it involved colorful rocks or water, but didn’t bother to research it beforehand. In the end, this may have been the best approach, since I was all the more surprised and impressed when I saw it.

As it turns out, Mammoth Hot Springs is actually a series of terraced springs formed from a combination of heat, water, and travertine. A geologist I am not, but a simple explanation of the process is this: A leftover magma chamber from an ancient volcanic eruption continues to heat the ground in the area. Numerous fissures in the rock allow hot water to flow up and out, thereby creating the 50 springs that make up Mammoth Hot Springs. Along with the water, calcium carbonate seeps from the limestone underground and, through a complex chemical process, results in travertine—the form of limestone that gives the terraces at Mammoth their unique and otherworldly appearance. Add to that various colonies of algae and bacteria that stain the formations in myriad hues, and voila! You have the hot springs as we see them (and smell them) today.

Accessing the springs is an easy feat since the area was designed for people to see them. The Mammoth Hot Springs Hotel and Cabins is more or less at the base of the springs and is the only place to stay in that part of the park. My boyfriend and I stayed in the hotel for one night. Sure, it looked like the hotel from The Shining inside and we shared a bathroom with other people, but these are the things one comes to accept when seeing natural wonders. The resident herd of elk that grazed on the lawn right in front of our window easily made up for any shortcomings!

We arrived in the late afternoon at the very end of August, checked in, and immediately set off for the famous springs, which are divided into the Lower and Upper Terraces. We opted to see the Lower ones first, which are accessible via a labyrinthine boardwalk system designed to protect you and the springs while allowing you to get as close as possible to the formations.

The first major stop starting from the bottom is Palette Springs, so named for the varied shades of brown, green, and orange that seep down this hillside much like an artist’s palette. Next to this is the bleached Devil’s Thumb formation, which resembles large mounds of oddly shaped meringue.

Another notable stop along the boardwalk is Main Terrace with its desolate apocalyptic landscape and gnarled dead trees.

Main Terrace

A short walk beyond that is Canary Spring, a waterfall of travertine that appears to cascade down a hillside in shades of yellow, gold, and white.

Canary Spring

In addition to the colors and strange ribbonlike travertine formations, there is the constant presence of sulfurous steam, which adds to the unreal atmosphere. I have a pretty sensitive nose, but I think I was so enthralled by the strange beauty around us, that I was able to block out the rotten egg odor.

The following day, we visited the Upper Terrace, which is accessed on a loop road instead of a boardwalk. These springs were slightly less stunning to me, but still worth a look. Orange Spring Mound rises up like a miniature multicolored volcano, while Angel Terrace looks more like the remains of a ghostly burned forest.

Orange Spring Mound

We ended our tour by driving down below Canary Spring, where elk graze, seemingly oblivious to the bizarre geological wonders around them.

There are plenty of other unique features in Yellowstone—geysers, mud pots, pools of boiling water—but Mammoth Hot Springs was the one that pulled me in the most. It’s a must-see destination for anyone planning a trip to Yellowstone.