“One of Yellowstone's oldest trails climbs 700 feet up to Swan Lake Flat.”
— Tom Carter
The Snow Pass Trail begins from a poorly marked trailhead on the Mammoth to Norris Road a few miles south of Mammoth Hot Springs. The trail climbs (steeply in places) up more than 700 feet to the pass and ends at its junction with the Glen Creek Trail
The trail immediately begins its climb and at the .1-mile mark crosses the Howard Eaton Trail. It continues climbing through heavy forest and at the 1-mile mark passes the Clagett Butte Trail
(on the right). From there, the trail climbs more steeply and eventually breaks out of the trees before reaching Snow Pass at the 1.5-mile mark.
The trail through Snow Pass (also known as “Hell’s Gate”) is one of the oldest trails in Yellowstone. Park Superintendent Philestus Norris discovered the pass in 1875 and built the first road into the interior of the park in 1878 using this pass. For 5 years horses and later stagecoaches used this route to reach the hot springs and geysers around Old Faithful. But the trail was too steep, and in 1883 a new road was engineered through the Golden Gate, along the route followed by today’s highway.
From the pass, it’s another .6 miles over fairly level terrain to a junction with the Glen Creek Trail
. Near the end, the trail breaks out onto the northern end of Swan Lake Flat and affords nice views to the south along the front of the Gallatin Mountain Range.
Thanks to guidebook author, Tom Carter, for sharing this trail description. To learn more about visiting Yellowstone, check out his book, Day Hiking Yellowstone