Endurance Grid lists 10 ultramarathons in California, from September 2026 to April 2027 across 10 cities.
The lay of the land
The ultramarathon race calendar in California is busiest in October, January, and April, with races most often in Napa, San Diego, and San Francisco.
An ultramarathon is any running race longer than 26.2 miles. The most common distances are the 50K, 50-mile, 100K, and 100-mile — alongside timed events, where you cover as much ground as you can in a fixed window like 6, 12, or 24 hours.
Many ultras run on trails, with aid stations stocked with food, water, and posted cutoff times. For most entrants the goal is to finish, not to race the clock, and hiking the climbs is a normal part of the day.
Frequently Asked Questions (FAQs)
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