Trail

Glacial Boulder Trailhead

TrailOPERATIONAL★ 4.4
Glacial Boulder Trailhead at Yellowstone National Park framed by tall pines and a massive glacial boulder

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.

Quick facts

Distance Miles
10
Route Type
Out-and-back
Difficulty Level
Strenuous
Elevation Gain Feet
1200

Trail profile

Distance Miles
10
Route Type
Out-and-back
Difficulty Level
Strenuous
Elevation Gain Feet
1200
Estimated Time
6-8 hours
Trail Surface
Primarily forest; some canyon rim sections; uneven footing; potential hot spring areas
Trail Features
  • Glacial Boulder
  • Silver Cord Cascade
  • Yellowstone River views
  • Canyon rim sections
  • Nearby hot springs exposure
Trail Highlights
Silver Cord Cascade, the Yellowstone River viewpoints, and panoramic perspectives from Mount Washburn via the spur

Trailhead & access

Trailhead Location
Glacial Boulder pullout on the road to Inspiration Point, Grand Canyon of the Yellowstone
Parking Lot Size
No dedicated parking; roadside pull-off
Parking Fill Time
Parking spots typically available early; arrive by 7:30 AM to secure a spot
Shuttle Required
0
Shuttle Details
No shuttle required

Permits & conditions

Permits Required
Yes
Permit Details
Overnight camping, fishing, boating, and riding require permits; day hiking does not. Contact the Backcountry Office at (307) 344-2160 for info
Fees
Park entrance fees apply; permit costs vary by activity
Trail Status
Open

Facilities & rules

Restrooms At Trailhead
0
Water Sources
Yellowstone River is the only reliable source on Seven Mile Hole; filtration required; carry ample water for Mount Washburn Spur

Safety & strategy

Hazards
  • Grizzly bears
  • Hot springs exposure
  • Steep canyon rim drop-offs
  • Unpredictable Yellowstone weather
  • Limited cell service
Hazard Details
Carry bear spray; travel in groups; stay on marked trails near hot springs; monitor weather; have navigation ready as cell service is unreliable
Cell Service
Unreliable
Crowd Level
Light to moderate; parking limits keep crowds low at the trailhead
Peak Crowd Times
Mornings on weekends; holidays
Best Season
Summer (June–August)
Best Time To Visit
Start early in the day. In summer (June–August) the weather is generally favorable, but be prepared for afternoon thunderstorms.
Tips Advice
  • 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.

More details

Park Area
Yellowstone National Park, Wyoming
Trail Markers
Trail markers present; carry map and compass
Shade Level
Partial canopy; some exposed sections
Emergency Contacts
Backcountry Office: (307) 344-2160; seek local ranger assistance in an emergency
Map Recommended
1
Alltrails Link
www.alltrails.com
Snow Dates
Snow can linger into late May or early June at lower elevations, later at higher elevations
Mud Season
Spring (March–May) can be wet and muddy
Bug Season
Mosquitoes most active during summer
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.
Family Friendly Notes
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
Review Summary
Hikers value the Glacial Boulder’s educational aspect and the canyon views; the hike is challenging and rewarding but parking is tight and the Seven Mile Hole trail is demanding. The grit score is high due to elevation changes and wildlife hazards.

Location

Glacial Boulder Trailhead at Yellowstone National Park reveals a snowy slope with rugged boulders and pine forest.Glacial Boulder Trailhead at Yellowstone National Park offers a view of snow-covered slopes framed by pines.Glacial Boulder Trailhead overlooks a rugged, sunlit canyon with pine forests along the rim, in Yellowstone National Park.Glacial Boulder Trailhead in Yellowstone National Park features fractured soil, exposed roots, and weathered, stunted pines.

Frequently asked questions

Are bears a concern on these trails?

Yes. Bear spray is mandatory; travel in groups, stay on trails, make noise, and store food properly.

Do day hikers need a permit?

No permit required for day hiking; permits are needed for overnight camping, fishing, boating, and riding.

Is parking guaranteed at Glacial Boulder?

No. Parking is limited to roadside pull-offs; arrive early or plan to park along the road and walk in.

Is cell service reliable back here?

No. Expect poor to no service; carry navigation tools and share your plan with someone.

What should I bring for water?

Filter water if you plan to use any from the Yellowstone River; otherwise carry ample water (2+ liters) and plan for mountaintop supply gaps.

Brink of Lower Falls

0.7 miles out-and-back. Steep climb back. The brink of Lower Falls rewards the grit.

Sources

Information is compiled from official sources, verified traveler reviews, and editorial research. Learn how YourNPGuide works.

Last updated January 2026. Report an issue.