San Diego 100 Mile Endurance Run

San Diego 100 Mile Endurance Run sets off at 6:00 a.m. on April 30, 2027, from Mount Laguna, in the mountainous backcountry of San Diego County, California. One event is on the program: a 100-mile trail race, or 160.9 kilometers.

A hundred miles is not a stretched marathon and cannot be trained for like one. It asks for a year of building, back-to-back long runs on consecutive days, comfort with running through the night and specific work on fast uphill hiking, which is what you will actually be doing on the climbs. Logistics count as much as fitness here: write your fueling plan down, prepare drop bags in advance and brief anyone crewing or pacing you. A 6:00 a.m. start also means you will be running into the following night, so get used to moving by headlamp well before race week.