A short steep sprint to one of Yellowstone’s smaller and lesser known thermal areas, Monument Geyser Basin. Although most of the geysers are now dormant, their forms are unusual and worth a visit. Monument Geyser, the largest geyser of them all, still puts on a show, emitting regular puffs of steam and boiling water. The 600-feet climb up to the basin also affords fantastic views of Gibbon Canyon, the flat grasslands of Gibbon Meadow, and in the distance you may be lucky enough to see steam clouds rising above Norris Geyser Basin on a clear day.
Find the signed trailhead in a carpark next to a bridge over the Gibbon River, 8.6 miles from Madison Junction and 4.5 miles south of Norris. The Monument Geyser Basin Trail starts off gently, taking you through the trees along the edge of the canyon, its relatively flat until it descends to the river after 0.3 miles. Once you reach the far end of the valley, the trail sharply turns southwest and ascends the hillside, steeply climbing up a sloping grey rhyolite rock face. Be careful with your footing as the surface is loose and slippery. The views get better and better as you climb, as the trees begin to fall away and the river canyon and meadows become visible. The trail leads you to a viewpoint of the basin, where a sulphurous smell permeates the air, and the unstable ground emits hissing and bubbling noises from numerous small fumaroles, vents and mud-pots, both hot and acidic. The largest and most impressive feature is Monument Geyser, at 8 feet high, it regularly produces puffs of steam and boiling water. The surrounding geysers are dormant, but have curious formations which have been aptly named after their shapes- Sperm Whale, Sunning Seal, Jumping Seal, Dog’s Head and Dog’s Tail. Turn back around and follow your steps right back to the trailhead when you’re done.