Mammoth Hot Springs

Mammoth Hot Springs is a series of thermal terraces in Yellowstone National Park featuring white limestone steps filled with mineral-rich water reaching about 165 degrees Fahrenheit (74°C). The calcium carbonate deposits form layered, stepped formations that look like stacked pools cascading down a hillside.

Native peoples used these springs for centuries before Fort Yellowstone was established in 1886 as a military outpost. The fort served as the U.S. Army headquarters until 1918, helping protect the park from damage and illegal activity.

Native American tribes including the Blackfeet, Crow, and Shoshone held these springs as sacred places for healing and gathering. Even today, the site carries that sense of being a place where people felt connected to something larger.

Visitors can explore two miles of elevated boardwalks winding through the terrace complex, offering safe and close views of the hot springs. The paths are well-maintained and allow visitors to choose shorter or longer routes depending on their comfort level.

The springs deposit roughly two tons of travertine limestone daily, continuously reshaping the terraces and creating new formations at a surprisingly rapid pace. This ongoing transformation means the hillside looks noticeably different from year to year in unexpected ways.

Location: Park County

GPS coordinates: 44.97062,-110.70564

Latest update: December 6, 2025 21:20