No permit required, but the park entrance fee applies ($35 per vehicle, 7-day pass, or $20 per person on foot/bike).

Bunsen Peak Loop - 10mi Strenuous Bike Trail

Q: Can I ride this on a road bike?

No. The dirt road is chunky, the descent is technical with sharp drop-offs, and road bike tires will lose traction. Mountain bikes are essential.

Q: Is the parking really that tight?

Yes—the lot fills by 7am most summer days. Arrive by 5:30am or risk wasting your drive. There are no overflow lots or shuttle alternatives.

Q: How much water do I need?

3 liters minimum. The trail is exposed with zero water sources. Dehydration kills your ride and your judgment around wildlife.

Q: What if I can't finish the full loop?

The Osprey Falls alternative (6.5 miles round trip) is much gentler. Or do an out-and-back from Bunsen Peak trailhead for as long as you want.

Q: What if I'm alone—is that safe?

Solo travel is possible, but tell someone your plan and expected return time. Carry bear spray, a map, and full water. Know your fitness limits and that emergency response is slow in the backcountry.

Distance

10 mi

Elevation Gain

1,120 ft

Est. Time

4–6 hours, depending on fitness and rest at viewpoints

Route Type

Loop

Dogs Allowed

Best Season

Summer and Fall

Overview

About This Trail

This is a ten-mile mountain bike loop through grizzly country with 1,120 feet of elevation gain—strenuous and technical. The first three miles are deceptive: flat dirt road that lulls you into false confidence. Then the northeast face turns vicious, dropping 960 feet in 2.5 miles with sharp curves and cliff-edge exposure demanding full control. Expert riders only, summer and fall. Bring bear spray and arrive before dawn.

Highlights

Difficulty Level

Strenuous

Trail Highlights

The payoff is the northeast descent: screaming down 960 feet of technical dirt with perfect control through cliff-edge curves. Views of the thermal landscape and Bunsen Peak reward you at multiple points. The final 1,000-foot climb back to the main road is the real battle—grinding fitness and mental grit.

Insider Tips

• The false summit at mile 4 feels like the end—it's not. Push through to the final descent. • The Osprey Falls alternative (6.5 miles round trip from Bunsen Peak trailhead) is much gentler for warm-ups or bailouts. • Descending after 10am risks finishing in fading light—not ideal. • Glen Creek drainage is the steepest, most technical section. Use full braking control, lean back, and respect the exposure.

Best Season to Hike

Summer and Fall

Hiking Tips

Tighten your boots before the technical sections—ankles take abuse on the drop-offs.
Bear spray on your hip belt, not your pack. Know how to use it.
Carry 3 liters of water minimum—the expose on the return climb is relentless.
Start by 5:30am. Parking is non-existent by mid-morning.
Mountain bikes mandatory; road bikes will wash out and kill you.
Stay 100 yards from bears/wolves, 25 yards from bison and elk.
The descent is technical and fast—full control required on every curve.

Family Info

NOT family-friendly. The steep descents (950 feet in 2.5 miles) and cliff-edge drop-offs make this unsuitable for children and inexperienced riders. Drop-offs are severe and exposure is real.

What Hikers Say

Riders call this a lung-buster with real exposure. The first half on flat dirt is manageable; the second half (960-foot descent plus 1,000-foot climb) separates the fit from the struggling. Most agree: expert technical skill and fitness required. Do not attempt if you're new to mountain biking.

Details

Trail Specifications

Distance: 10 miles

Elevation Gain: 1,120 ft

Duration: 4–6 hours, depending on fitness and rest at viewpoints

Difficulty: Strenuous

Route Type: Loop

Surface: Mostly dirt road and gravel, with chunky, technical sections on the descent

Getting There

Trailhead: Bunsen Peak Trailhead, north of Mammoth Hot Springs

Parking: Limited—approximately 15–20 spaces

Fills Up: By 7am during peak summer months

Requirements

Permit Required

No permit required; park entrance fee applies

Fees: $35 per private vehicle (7-day pass) or $20 per person on foot/bike

Shuttle Available

No shuttle service available

Trail Rules

Dogs: No, not permitted

Biking: Yes—required. Mountain bikes essential; road bikes not suitable.

Trail Markers: Well-worn dirt road, easy to follow the main loop. Some sections less distinct—map recommended.

Map/GPS recommended

Trail Features

Conditions & Safety

Water: None on trail. Carry all water from the trailhead.

Shade: Mostly exposed, especially on the descent and return climb

Cell Service: Unreliable; no service guarantee in backcountry

Hazards:

Grizzly and black bears are active—bear spray mandatory, and you must know how to deploy it. Stay 100 yards from bears/wolves and 25 yards from bison and elk. Sharp, abrupt drop-offs are common, especially on the northeast descent; cliff-edge curves demand technical control. The 960-foot drop in 2.5 miles and 1,120-foot overall gain test fitness and nerve.

Emergency: Mammoth District Ranger Station (nearest emergency contact). Call 911 if within cell range; otherwise, return to trailhead immediately.

Crowd Info

Typical Crowds: Moderate to busy during peak summer, limited by scarce parking

Peak Times: 7am–10am during June through August; weekends year-round (within season)

Accessibility & Family

Accessibility:

First 3 miles: mostly flat dirt road, potentially rideable by hand-cycle with mountain bike tires. Remaining 7 miles: very steep, technical, with sharp drop-offs and abrupt curves—NOT suitable for casual riders, novices, or those with vertigo. Service dogs permitted but face increased wildlife risk in backcountry.

Family Notes:

NOT family-friendly. The steep descents (950 feet in 2.5 miles) and cliff-edge drop-offs make this unsuitable for children and inexperienced riders. Drop-offs are severe and exposure is real.

Nearby Facilities

Mammoth Hot Springs offers lodging, dining, and ranger services. Nearest campground: Mammoth Campground.

What Hikers Say

FAQs

Are there really bears?

Yes—grizzly and black bears are active in this area. Bear spray is mandatory; carry it on your hip belt and know how to deploy it. Stay 100 yards away if you see one.

Can I ride this on a road bike?

Is the parking really that tight?

How much water do I need?

What if I can't finish the full loop?

Do I need a permit?

What if I'm alone—is that safe?

🏞️ National Park Service 📝 YourNPGuide Editorial

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

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