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Glacial Boulder Trailhead
Last Updated: January 2026
Overview
About This Trail
From the Glacial Boulder pullout, Seven Mile Hole Trail runs 10 miles round-trip with a 1,200 ft vertical. The route is out-and-back, mostly through forest with sections near the canyon rim and some uneven footing. Hydration and bear spray are non-negotiable; prepare for backcountry weather that can shift in minutes. Start early and plan for 6-8 hours of hard work.
Highlights
Difficulty Level
Strenuous
Trail Highlights
Silver Cord Cascade, the Yellowstone River viewpoints, and panoramic perspectives from Mount Washburn via the spur
Insider Tips
• For Seven Mile Hole, expect a sustained climb on the return; pace yourself. • Start early to avoid afternoon storms. • Bear spray should be readily accessible; keep food secured. • Use the Yellowstone River for water only with proper filtration.
Best Season to Hike
Summer (June–August)
Hiking Tips
- Carry at least 2 liters of water; filter the Yellowstone River if used on Seven Mile Hole.
- Bear spray is mandatory and easily accessible.
- Wear sturdy boots, bring layers, rain gear, map, and compass; trekking poles help on steep sections.
- Start early to beat storms and heat; monitor weather and turn back if conditions worsen.
- Cell service is unreliable; carry a navigation plan and share your route.
Family Info
Seven Mile Hole Trail is strenuous and not suitable for young children or those with health concerns; Mount Washburn Spur is also a significant undertaking
ℹ️ Data Sources
naturalatlas.com nps.gov lonelyplanet.com wanderlog.com Current time information in Gallatin County, US. Google Reviews National Park Service YourNPGuide Editorial
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