13 miles, 3,400 feet — welcome to Mammoth vert

No Service Requirement

Does not require trail or volunteer work

No qualifier race required

Some ultra experience recommended

The Mammoth Bar Half Marathon packs approximately 3,400 feet of elevation gain into 13.1 miles of singletrack and OHV doubletrack above the American River Canyon. Two aid stations support runners on the relentlessly steep climbs and descents that define this course. No crew or pacers are allowed; runners must be self-supported between aid stations. Trekking poles are permitted.

Exceptional vert-to-distance ratio on the OHV trails above the American River Canyon

Courses traverse the canyon walls above the Middle Fork American River near Auburn, CA

Inaugural edition launched September 2025 in the self-proclaimed Endurance Capital of the World

Mixes true singletrack with rugged OHV doubletrack through Mammoth Bar OHV Area

This event uses open registration - no lottery entry required.

This event does not require a qualifier for entry.

This race does not have a service requirement for entry.

No Service Requirement

Does not require trail or volunteer work

No qualifier race required

Some ultra experience recommended

Exceptional vert-to-distance ratio on the OHV trails above the American River Canyon

Courses traverse the canyon walls above the Middle Fork American River near Auburn, CA

Inaugural edition launched September 2025 in the self-proclaimed Endurance Capital of the World

Mixes true singletrack with rugged OHV doubletrack through Mammoth Bar OHV Area

This event uses open registration - no lottery entry required.

This event does not require a qualifier for entry.

This race does not have a service requirement for entry.

Location	Mile	Elevation
Start Start	0.0	617 ft
Castle Rock Aid (outbound) Aid Station	2.0	1,493 ft
F.D.L. Aid Aid Station	5.0	1,693 ft
Castle Rock Aid (return) Aid Station	11.3	1,493 ft
Finish Finish	13.1	617 ft

Location	Mile	Elevation
Start Start	0.0	617 ft
Castle Rock Aid (outbound) Aid Station	2.0	1,493 ft
F.D.L. Aid Aid Station	5.0	1,693 ft
Castle Rock Aid (return) Aid Station	11.3	1,493 ft
Finish Finish	13.1	617 ft

Mammoth Bar Half Marathon

Nearby races

Mammoth Bar 10K

Canyons 100 Mile

Rio Del Lago 100 Mile

Signal Peak Trail Runs 50K

Broken Arrow Skyrace 46K

Western States Endurance Run

Tahoe 200 Endurance Run

Tahoe Rim Trail Endurance Runs 100 Mile

Mammoth Bar Half Marathon

What Makes It Great

Difficulty

Race Highlights

Finish Awards