The 2021 event starts on Friday, June 4, 2021 at 6:00 AM
The Premier 100 Mile Running Event in San Diego
Scenic & Challenging 100 Miles in Mt Laguna Recreational Area and along the Pacific Crest, Noble Canyon, and Lake Cuyamaca Trails. This is the 20th annual event.

2020 San Diego 100 is cancelled. We are already full for 2021, but will open a waitlist on January 1 at 12:01 AM for the 2021 edition of the race. If you have any questions, please contact us at Thanks, and see you in 2021!

Qualification requirements to enter the 2020 event are as follows:
Applicants must have completed an official 50 mile race in 13 hours or less or a 100k or 100 mile race between January 1, 2018 and March 15, 2020. If a lottery is required, priority will be given to those runners who have completed their qualifying race. Should there be a lottery, runners signing up during the lottery signup without a qualifier will be placed on the waitlist and will keep their place on the waitlist and/or be granted entry pending their completion of the qualifier. No lottery has been necessary since the race expanded its field to 300 runners, but last year we were full by January 10, so we encourage you to sign up early. SURF members of at least 3 months good standing receive an extra ticket in the lottery should one be necessary. Volunteers who gave 6 hours or more to the race the prior year receive a lottery bypass. The race directors reserve the right to grant up to 10 entries to runners who have performed outstanding work for the SD 100 or contributions to the field of trailrunning.

We will accept applications on Ultrasignup beginning 1/1/2020 through the deadline of midnight of 1/4/2020. A lottery will take place if over 300 qualified applications are received. If there are less than 300 applicants, entries will reopen on Ultrasignup on 1/5/2020 until the 300 person limit is reached. A waitlist will be maintained on Ultrasignup once the field limit of 300 is reached. The latest date for wait listed applicants to receive a slot is April 15, 2020. After that date, there will be no refunds for entrants and no other applicants will be accepted.


All entrants are required to perform 6 hours of volunteer work within the year prior to the start of the 2020 race as a requisite to participate or donate $100 to the SURF Mount Laguna sign project in lieu of their volunteer hours. We encourage entrants to volunteer through trail work on your local trails or the trails in the Mount Laguna District of the Cleveland National Forest where the San Diego 100 is largely run, but volunteering at an ultra or other race is acceptable. Please see our volunteer page for further information.

SD 100 is a Cupless event

Please support our sponsors and check out their products:

San Diego 100 operates under permit on the Cleveland National Forest.

"USDA and the San Diego 100 is an equal opportunity provider, employer, and lender."

Lake Cuyamaca, California, USA

2019 Race Photos: Howie Stern

Runner Racebook:
Now available

Interactive Map

San Diego 100 2019 = 5 points