The first Angeles Crest 100 was held in September 1986.
Race Management has worked to preserve the original point-to-point route from Wrightwood to Altadena, while adapting to the realities of fire damage, trail closures, and wilderness protections. Over the years, the course has seen temporary reroutes — but the spirit and challenge of the AC100 remain unchanged.
The 36th annual Angeles Crest 100 will be held on October 3, 2026 — the first October race since 2008. With cooler temps and improved trail access, we aim to return to the full point-to-point course from Wrightwood to Altadena, conditions permitting.
After fire damage to both ends of the route, the 2025 race used an out-and-back format for safety. As the forest continues to recover, we’re optimistic about bringing back the historic course runners know and love.
Due to extensive fire damage in both the opening and final sections of the traditional point-to-point route, the 2025 race returned to the “Out-and-Back” course first used in 2022. The Eaton Fire (January 2025) closed trails near Altadena, while the Bridge Fire (September 2024) impacted the Acorn Trail and Blue Ridge near Wrightwood. Thankfully, the front half had recently reopened in time for race day.
This high-altitude route added elevation and technical challenge, prompting a 36-hour time limit. Runners could earn either the new 36-hour Solid Bronze Buckle or the traditional 33-hour version.
In 2024, AC100 finished in Altadena via Kenyon/Devore Trail to the top of Mt Wilson, bypassing Chantry. The race passed through Shortcut on the Edison Road to Newcomb Saddle. After Newcomb Saddle, it followed the Rincon-Redbox Road through West Fork Campground to Redbox. From Redbox, it takes the Gabrielino Trail to the Kenyon Devore Trailhead. Runners ascend the Kenyon Devore Trail to the top of Mt Wilson, then to Idlehour, Sam Merrill, Millard, and Loma Alta Park in Altadena. There is an interactive map on the Full Course Page.
2018 AC100 Chantry Aid Station. Photo: Foothill Flyers.
2022 AC100 Dominic Grossman and Michael Eastburn.
The Bobcat Fire of 2020 torched many areas of the course, as runners will begin to see approaching Islip Saddle. Due to excessive damage from the fire and subsequent rainstorms on the trail through Chantry Flats, Newcomb Saddle, Redbox and Shortcut Saddle, trail access remains closed. After two years of cancellations due to the COVID-19 pandemic and fire, the decision was made to host an out-and-back course from Wrightwood to Shortcut Saddle and back – a worthy challenge for all who have missed the San Gabriels. We have every intention of returning to the point-to-point course in the future, as the forest allows.
Since 1986 the Angeles Crest 100 was held annually in late September/early October. After the devastation of the 2009 Station Fire and years of drought, the decision was made to move the race to the first weekend in August, in the hopes of avoiding fire season. While the race is undoubtedly a bit more challenging in the Southern California summer heat, the race has not been canceled since.
2019 AC100 Jorge Pacheco in the Mt. Williamson Tunnels. Photo: Run Vertical Productions.
With the expansion of the Pleasant View Wilderness (PVW) came a major course update in 2016. No longer allowed to use the PCT section in the PVW from Islip Saddle over Mt. Williamson, the race now utilizes the shoulder of Highway 2 until rejoining the trail over Kratka Ridge, lovingly referred to by local runners as the “scenic mound.” The current course between the Islip Saddle and Eagle’s Roost is now a 2.5-mile section of pavement that travels through the Williamson Tunnels.
The original Cooper Canyon section was updated in 2005 when environmental concerns over the endangered Mountain Yellow-legged Frog closed a section of the PCT leaving Eagle’s Roost. Runners instead traveled the shoulder of paved Highway 2 to the exit of Buckhorn Campground, which they ran through to join the Burkhart Trail to Cooper Canyon Trail Camp. For a number of years, the course then took a “death march” up a fire road until rejoining the trail for the final ascent up to Cloudburst Summit, but was replaced by a section of the PCT, adding a mile but also a lot more scenery (and maybe even a slight breeze). Awaiting the outcome of an Environmental Impact Report regarding the Mountain Yellow-legged Frog, the intent has always been to return to the original course through the infamous inferno that is Cooper Canyon, however the same Pleasant View Wilderness expansion that disallowed the race to travel over Mt. Williamson has also barred us from entering Cooper Canyon at all. For the foreseeable future, the course must continue for 4.6 miles on the asphalt of Highway 2 all the way to Cloudburst Summit.
Photo: James Townsend.
Max Jolliffe on Highway 2 during the 2025 Angeles Crest 100. Photo: Orlando Baez.
Sean Lee during the 2025 Angeles Crest 100 Mile Endurance Run as he traverses the single-track trail of Mt. Hillyer. Photo: Orlando Baez.
Runner during the 2019 Angeles Crest 100 Mile Ultra Marathon as he ascends to the Redbox Aid Station. Photo: Run Vertical Productions.
In 2016, environmental concerns over the endangered Arroyo Toad habitat closed access to the Edison fire road where it crosses the West Fork of the San Gabriel River. Leaving the Shortcut Aid Station, runners now use the Silver Moccasin Trail down to West Fork, turning on the Gabrielino Trail which ascends to the new aid station and crew access point at Red Box. From there, the course travels back down to West Fork via the unpaved Rincon Red Box forest road, continuing directly up to the aid station Newcomb’s Saddle. Adding 8.5 miles and 1,300’ of gain, this new section makes up for the elevation lost over the removal of the Mt. Williamson, Cooper Canyon and Mt. Hilyer climbs and the cumulative mileage lost between Islip Saddle and Three Points. With the added climbing, heat and technical nature of the trail, most runners believe this has made the course significantly more difficult, and truer to the spirit of the original 1986 course.
1986 – Inaugural race; finished at the Rose Bowl. In 1992, it was replaced by Johnson Field due to a Guns N’ Roses concert. This resulted in the course being shortened from 101.9 miles to 100.2 miles.
The current finish line at Loma Alta Park was adopted in 2008, but the overall distance of the course remains the same as the 1992 edition.
As with many historical races, course changes throughout the years have sometimes made it difficult to accurately compare finishing times for the purposes of records. The original course length was 101.9 miles with 20,610’ of elevation change, while the modern course is 100.2 miles and 19,930’, and contains 7 miles of road running. On paper, it would seem fair to say the original course was more difficult. However, many seasoned AC runners note that while the return to a cooler October date has slightly reduced heat-related strain, ongoing trail degradation, decreased tree cover, and the addition of new, more technical reroutes caused by fire, drought, and wilderness designations have preserved — and in some sections even increased — the race’s overall difficulty.
Jim O’Brien, Hal Winton and Jussi Hamalainen at the 2014 finish line, celebrating Jim’s then 25-year-old record.
Angeles Crest 100 2016 Co-Race Director Hal Winton. Photo: Dahiya.
Continuing the tireless work of Hal Winton, rest assured that we are working year-round to keep the Angeles Crest 100 in business and reduce the amount of mileage this trail race is forced to run on pavement. By fostering relationships with the United States Forest Service through trail service and stewardship, taking an active role in our communities and other special interest groups and lobbying local politicians, we are committed to preserving and restoring the historic Angeles Crest 100 course. Over the past few years, an all-volunteer group formed dedicated to fostering work for play relationships between trail running events and public land management. Their first project is working to return the AC100 to the original course and secure passage along the historic route in perpetuity.
