Climb Spirit Mountain, Montana: 3 Routes to the Summit with Beartooth Mountain Guides

View of Spirit Mountain's North East Ridge from Black Canyon Lake

Spirit Mountain (12,288 ft) is one of the most sought-after alpine summits in the Beartooth Mountains of Montana. Towering above Moon and Glacier Lakes, this granite giant offers climbers a choice of three unforgettable routes, each with its own character—ranging from scenic alpine hiking to full-scale multi-pitch rock climbing.

At Beartooth Mountain Guides, we specialize in guided climbing trips on Spirit Mountain, including the iconic Lunar Arete route. Whether you’re looking for your first big summit or your next alpine adventure, here’s everything you need to know about reaching the top of this Beartooth classic.

South Slopes – The Classic Non-Technical Summit Route (Class 2–3+)

Spirit Mountain view from the Moon Lake approach

Best for: Fit hikers and backpackers looking for a non-technical summit with a big mountain feel.

• Route Description: This is the least technical and most accessible way to reach the summit of Spirit Mountain. Starting from the Rock Creek Trailhead, we approach via a network of alpine lakes around Glacier Lake. The most common way is to navigate the eastern shore of Glacier Lake and start hiking up the inlet stream. Look for the lowest angle in terrain while approaching on the South Slope. You might encounter snowfields early season and lots of talus all season.

• Total Distance: ~14 miles round trip

• Elevation Gain: ~4300 ft

• Season: July–September

Why go guided? Even though the route is non-technical, a guide helps with route finding, pacing, and safety on steep snow or loose terrain—especially if you’re new to high-altitude environments.

Northeast Ridge – Exposed Scrambling  (Class 4–5.4)

View on to the ridge with climber on the 5.5 pitch

Best for: Scramblers and climbers looking for a more adventurous route with dramatic exposure.

• Route Description: The Northeast Ridge provides an exciting alpine experience with sections of 4th and low-5th class climbing. Expect airy ridgeline exposure, route-finding challenges, and incredible views throughout. Once you entered the route from the saddle, pick your way through big blocks and find the most stable way to access the ridgeline. From here you continue to follow the ridge until you get pushed to the right (North) and are lower then the ridge again. Here you will encounter a few 4^th class steps with exposure. After the terrain eases back to 3^rd class gain the ridgeline again. From the ridgeline you will find a low 5^th class slab that leads either to a 5.5 short dihedral pitch or further to the right, an exposed constriction that leads into a gully. Both ways meet at the ridgeline again, keep climbing up 2^nd class terrain. Avoid the steeper terrain on tower-features above you and traverse left towards the couloir. At the couloir, climb up loose 4^th class rock (don’t enter the couloir) and gain a low 5^th -4^th class slab on excellent rock. From here different options have been described, and the easiest way we found was gaining the ridgeline again and staying left (west) of the exposed Gendarmes in low 5^th class terrain on blocky features. Once you gain the ridgeline again, exit on the east side on easy 2^nd class terrain, all the way to the plateau. From here, it is a short flat hike to the “Peak”.

• Approach: Start at Rock Creek THD/ Glacier Lake THD and go up the switchbacks. At some point (switchback 7 or so) leave the trail and follow Moon creek up river. You will pass Shelf Lake and Moon Lake before going up the steep NE saddle of Spirit Mountain. Navigate talus on morraines and potential snowfields. When you’re at the top of the saddle start looking for an entry of the route on stable rock.

• Descent: Many options exit, either descent Frosty Bowl (corniced snowfield), the South Slopes or 3^rd and 4^th class buttress feature just two buttresses down of Frosty Bowl.

• Protection: We recommend rope and light alpine gear, especially for the exposed sections.

Why go guided? Our guides provide technical instruction, belayed climbing where necessary, and manage route safety so you can enjoy the exposure without stress.

Lunar Arete – Montana’s Longest Alpine Rock Route (5.9, 12 Pitches)

Climber on Pitch ... on Lunar Arete

Best for: Experienced climbers seeking a classic alpine rock climb in the heart of the Beartooths.

• Route Overview: The Lunar Arete on Spirit Mountain is one of the finest alpine climbing routes in Montana. With 12 pitches of moderate granite climbing (mostly 5.5–5.7), this exposed ridge takes you from the shores of Moon Lake all the way to the summit.

• Full route description: read here in our blog post

• Climbing Style: Trad climbing, long simul or pitched sections, mixed alpine terrain

• Gear: Full alpine rack, ice axe and crampons for snowfields, helmet

Why go guided? The Lunar Arete is long, remote, and complex. Booking a guided Lunar Arete climb with Beartooth Mountain Guides ensures proper logistics, efficient route finding, and a high chance of success. This is a premier alpine climb that deserves expert support.

Route Comparison at a Glance

Route	Difficulty	Style	Best For
South Slopes	Class 2–3+	Alpine hike/snowfield	Strong hikers, first-time summiters
NE Ridge	Class 4–5.4	Scramble/exposed ridge	Experienced scramblers wanting a wilder line
Lunar Arete	5.7, 15 pitches	Alpine rock climb	Experienced climbers seeking a big line

Why Climb Spirit Mountain with Beartooth Mountain Guides?

• Local Expertise: Based in Red Lodge, MT, our guides know every corner of the Beartooth range.

• Custom Itineraries: We tailor each climb to your experience level and goals.

• Safety First: Our guides are professionally trained and provide risk management, technical coaching, and all necessary group gear.

• Wilderness Access: Let us handle bear safety, route planning, and overnight logistics.

Plan Your Spirit Mountain Climb Today

Whether you’re looking to hike the South Slopes, scramble the Northeast Ridge, or climb the Lunar Arete, we offer custom-guided trips throughout the summer season. Spirit Mountain is a true gem of the Beartooths—and a summit you'll never forget.

👉 Book your Spirit Mountain climb now: www.beartoothguides.com/contact-us