Marin Ultra Challenge

Marin Ultra Challenge starts in Sausalito, California, on March 13, 2027, with two trail ultras: a 50-miler (80.5 km) leaving at 6:30 AM and a 50K (31.1 miles) at 7:00 AM. No elevation figures are published for either course. The event is put on by Inside Trail Racing.

Both distances are listed as trail races, so terrain rather than flat-road math will decide your pace — plan on finishing times well slower than a road equivalent. The 50K is a reasonable first ultra for anyone already completing trail half marathons, provided you are willing to hike when the ground tilts up and let the clock go. The 50-miler asks for considerably more: back-to-back long runs on similar ground, a rehearsed habit of eating every 30 to 45 minutes, and a first two hours that feel far too easy. A 6:30 AM start also means organizing your gear the night before.