San Diego 100-Mile Endurance Race

The 2024 timer will start soon…

*** 04 June 2023 – Well done to all runners, and a huge “Thank you!” to all the amazing volunteers. Preliminary results can be found on the “Live Update” link and will be posted on our “Results” page soon. Stay tuned for more information about the 2024 race! ***

*** 30 May 2023 – Live updates for the 2023 race can be found here ***

*** 30 May 2023: 30 May 2023 *** CHAMBERS AID STATION HAS A NEW LOCATION – Chambers is officially moved to Stonewall Mine. You can see this location on Google Maps, and it will be at approximately mile 12 after crossing the paved road and the pond re-route. Because we have been asked to keep our impact to a minimum at this popular site, this will be a scaled-down station with fluids and some light snacks, and you must check-in for timing purposes. The exact routing is still to be determined, but it should be at most a quarter-mile deviation from the current course.

*** 30 May 2023: Google Spreadsheet for pacing/planning ***

*** 29 May 2023: Revised Course Info for 2023 Race ***

*** 18 May 2023: Mandatory Briefing Video ****

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. The 21st annual event will begin: Friday, June 2nd, 2023, at 0600.

Registration for the 2023 race will open January 1 at 12:01 AM. If you have any questions, please contact us at Thanks, and see you in 2023!

A Must-Read for SD100 Participants: Walter Handloser’s 2018 SD100 Race Report

Howie Stern’s photos from the 2019 SD100 can be found: HERE.

Qualification requirements to enter the 2023 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, 2021 and March 15, 2023. 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 of 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 trail running.

We will accept applications on Ultrasignup beginning 1/1/2023 through the deadline of midnight of 1/4/2023. A lottery will take place if over 300 qualified applications are received. If there are fewer than 300 applicants, entries will reopen on Ultrasignup on 1/5/2023 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 waitlisted applicants to receive a slot is April 15, 2023. 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 2023 race as a requisite to participate or donate $100 to San Diego 100 to support the TrailFit Program 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.

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.”

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