This 1.6 mile groomed ski trail is one of the most enjoyable winter adventures in the park. It has commanding views of the area, takes you past a number of interesting hot springs, and provides chances to see animals including bison, elk, and mule deer. Cross-country skiers are advised to follow this loop trail beginning to the left (counter-clockwise) to get the biggest hill out of the way, then enjoy a mostly down-hill trip through the hot spring terraces. Snowshoers will want to travel clockwise, to see the most interesting views and features first. This description follows the clockwise route (turn right at the beginning of the loop trail).
Turn right an follow the groomed trail as it traces its course along the Upper Terrace Road through a sparse forest of Rocky Mountain Juniper trees. Soon the trail breaks out and affords commanding across the top of the main hot spring terrace to the Mammoth Hotel (to the left) and Fort Yellowstone (to the right). Fort Yellowstone was originally built by the US Calvary, who were in charge of protecting the park from 1886 until 1916, when the National Park Service was created.
In 2015, Baby Spring reemerged in this area and began overtaking the road! The Mammoth Hot Springs area is highly volatile and the springs here emerge, and dry-up, only to reemerge again. The calcium carbonate deposits brought to the surface by the springs in this area build up very fast, often growing many inches in a single year. This forces the NPS to move the boardwalks and sometimes the road to get out of the way of these natural features.
The trail loops back to the left and climbs a hill passing the remnants of New Highland Terrace on the left. At the top of the hill the trail rounds beautiful Orange Spring Mound. The trail then meanders past Highland Spring and eventually White Elephant Back Terrace (both on your left) before dropping down 170 feet to complete the loop.
Thanks to guidebook author, Tom Carter, for sharing this trail description. To learn more about visiting Yellowstone, check out his book, Day Hiking Yellowstone
The trees here are primarily Rocky Mountain Juniper, an evergreen with scale-like needles and many "berries," which are really small rounded female cones. Following pollination, its tiny seeds ripen, changing the cone's appearance from green to bluish-purple. These ripe cones are often eaten by birds. Interestingly, seeds that have been through the digestive tract of a fruit-eating bird or mammal germinate faster.