Sepulcher Mountain Trail

Overview

Sepulcher Mountain is a demanding 11-mile loop that earns its keep with panoramic summit views and a satisfying variety of terrain. Expect a sustained climb of roughly 3,400 feet to a 9,652-foot high point, then a long, scenic descent—classic Yellowstone big-country hiking. It’s strenuous, exposed up high, and far quieter than the Mammoth area below.

Route Snapshot

Most hikers start near Mammoth Hot Springs. A popular counterclockwise loop briefly follows Clematis Creek, then bears right at early junctions to climb through forest and meadows toward the summit. The upper mountain mixes volcanic boulder fields with steep switchbacks before topping out. The descent drops the broad south side to Glen Creek, then heads left (southeast) to a divide; take the left over Snow Pass, then stay attentive at subsequent splits to close the loop. Carry a good map or GPS—junctions around Snow Pass can trip people up in patchy snow or low visibility.

What You’ll See

From the top, the views sprawl across Mammoth Hot Springs, Mount Everts, the Absarokas, Swan Lake Flats, the Gallatin Range—and on the clearest days, even the Tetons. Along the way, look for the hoodoo-like volcanic formations that inspired the mountain’s name, open grasslands flecked with wildflowers, and stretches of lodgepole forest. Wildlife is a real possibility here: elk are common, and both black and grizzly bears use the area—give them space and be prepared.

Difficulty and Time

This is a strenuous, full-value day. Most strong hikers take about 6–8 hours; plan around 7 hours with steady breaks. The ascent is sustained, and the upper ridges can be windy with little shade. Early season can add lingering snow near the summit and on the east side.

Best Time to Hike

June through October is typically the sweet spot once snow recedes. Start early for cooler temps, calmer winds, and the best chance at afternoon storm avoidance. Weekdays see fewer hikers. Clear, post-frontal days deliver the best long-range views and photo light up high.

Logistics and Tips

• Navigation: Signage exists but isn’t foolproof—download an offline map and mind the Snow Pass junctions on the return.
• Water: Seasonal and limited. Carry what you need and treat any sources you find.
• Clothing/gear: Long pants help in shrubby sections; trekking poles are useful on the steep grades. Bring layers for wind and fast-changing weather.

Safety and Regulations

This is prime bear country. Hike in a group, make noise, carry bear spray and know how to use it, and give wildlife ample distance. Lightning is a real risk on the open upper mountain—don’t linger on ridges if storms build. No pets, no motorized use, and stay on established trails.