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Marin Ultra Challenge 50 Mile by Inside Trail Racing



51.0 mile 82.0 kilometer loop
87% Runnable


Ascent: 9,172' 2,796 m
Descent: -9,172' -2,796 m
High: 1,826' 557 m
Low: 12' 4 m


Avg Grade: 7% (4°)
Max Grade: 55% (29°)


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Trail shared by Tim Stahler

A beautiful and challenging coastal 50-mile trail race with hills and views galore.

Tim Stahler

Features River/Creek · Views · Wildflowers · Wildlife


The Marin Ultra Challenge, our premier Marin County long distance trail race, delivers ample hills and sweeping descents. March 14th marks the 4th edition of this tour of some of Marins best trails. Meticulous effort went into the design of each course for the MUC; all three distances are physically demanding (the 50 Mile has just about 11,000 feet of elevation gain) and exceptionally beautiful. The journey begins underneath the Golden Gate Bridge, then traverses the Marin Headlands, Stinson-facing Mt. Tamalpais and Muir Woods, exhibiting a range of terrain, from exposed fire-roads with incredible coastal and inland views to tight, technical singletrack with redwood canopies. There is very little trail overlap, and Jim Vernon, from The Endurables and Hydrapak, spent hours and weekends developing these spectacular custom courseswe are super excited to show it off. Youll quickly realize why Marin County has become a trail runners destination.


Starting just steps away from historic Fort Baker, in the shadow of the Golden Gate Bridge, runners may fill their lungs with fresh salt air before embarking on a journey through some of the best trails the Marin Headlands and Mt. Tamalpais has to offer, including the beautiful views of Coastal Trail, the inland buffed singletrack of the Miwok, descend on the famous Dipsea Trail and tackle one of the toughest climbs around Willow Camp.

Youll travel along the coast, by Pirates Cove, to Muir Beach. From there you'll cross over to Mt. Tam, climbing to the top of Cardiac Hill then scream down the Dipsea to Stinson Beach. Depart Stinson Beach with the 1,800 of vertical gain in 1.8 miles on Willow Camp and traverse Mt. Tam along the singletrack Coastal Trail, back to the top of Cardiac. Enjoy the tall trees as you pass through Muir Woods, before you climb back into the Headlands on Miwok to the killer downhill of Dias Ridge back to Muir Beach.

From there, youll quietly pass through the Zen center and up the incredible new Middle Green Gulch hill. Your journey will ultimately end with amazing vistas of San Francisco and the Golden Gate Bridge from the SCA and Coastal trails all the way back to the finish at Cavallo Point.

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