What’s Up in Ultra This Weekend — January 31, 2026

We bid adieu to January and welcome in February with 24 North American ultramarathons on the UltraRunning Magazine race calendar. In this week’s What’s Up in Ultra, we highlight events in California, Georgia, New Jersey and Yukon, Canada. If you’re a race director and would like your event to be featured in the calendar, register here.

Featured: Sean O’Brien (Malibu, CA)

The Sean O’Brien Trail Runs return to Malibu Creek State Park this weekend with three ultramarathon distances (100k, 50-mile and 50k) kicking off Saturday morning, January 31. One of California’s classic winter ultramarathons, the event takes place primarily on the famed Backbone Trail, a 67-mile continuous trail system that traverses the Santa Monica Mountains. Participants will enjoy spectacular ridgeline views of the Pacific Ocean while being challenged by long, sustained climbs and quad-pounding descents. Elevation gain for the three races includes approximately 6,300 feet in the 50k, 11,000 feet in the 50-miler and 13,000 feet in the 100k. All 100k finishers who complete the race in under 17 hours will earn a 2027 Western States Endurance Run qualifier. Read more about Sean O’Brien trail runs here.

Other West Events:

Pacific

• Jed Smith (Sacramento, CA)
• Winter Deception Pass (Oak Harbor, WA)

Mountain

• The Bootleg Boogie (Boulder City, NV)
• Bigfoot Snowshoe Festival (Midway, UT)
• Arches Ultra (Moab, UT)

No events this weekend.

Featured: Dark Anchor (Savannah, GA)

The fourth annual Dark Anchor is a 34-hour fixed-time event by Yeti Trail Runners that encourages participants to “refuse to sink” and run farther and longer than they ever have before. This year, the race drops anchor at a new port of call on scenic Jekyll Island, Georgia, where runners will tackle a flat, smooth and highly runnable 3-mile loop course. The event begins at 6 a.m. on Friday, January 30, and runners have until 4 p.m. on Saturday to log as many miles as possible. Official times are recorded for those who complete at least 25 kilometers, with all participants earning finisher medals and 100-mile finishers receiving special buckles. Read more about the 2026 Dark Anchor here.

Other South Events:

Southwest

• AZT Oracle Rumble (Tucson, AZ)
• Running the Rose (Tyler, TX)
• River Ranch Resolution Run (Liberty Hill, TX)

Southeast

• Forgotten Florida (Christmas, FL)
• Donna 110 Ultra Marathon (Jacksonville, FL)
• Coo-Wah-Chobee 50k (Venice, FL)
• The Thunder Run (Jacksonville Beach, FL)
• Live Oak Ultra (Biloxi, MS)
• Move: A Carbon Negative & Fat Ass Style Random Run (Huntersville, NC)
• Groundhog’s Lap Race (Greensboro, NC)
• HAROC (aka Hanging Rock Challenge) (Danbury, NC)
• Pleasant Ridge Backyard Ultra (Greenville, SC)
• The Great Frosty Forest (Dumfries, VA)

Featured: Frosty Squatchy (West Orange, NJ)

**Canceled due to weather**

The Frosty Squatchy Trail Party heads back to South Mountain Reservation in West Orange, New Jersey, for its ninth edition. The OG Sassquad Trail Running event, Frosty Squatchy is a fixed-time race offering 6-hour and 3-hour options. The event takes place on a 5k loop that blends hard-packed carriage trails with technical single-track and features roughly 300 feet of elevation gain and loss per loop. This is a fat-ass style event, meaning no swag or aid stations, so runners should bring all the nutrition they’ll need for the day. Race proceeds benefit South Mountain Reservation, and participants are encouraged to bring slightly used running and outdoor gear to donate to the Sassquad ReTrail Project. Learn more about the race and Sassquad Trail Running in the Frosty Squatchy Trail Party handbook.

Other Northeast Events:

• Devil’s Shadow Winter Trail Races (Honeoye Falls, NY)
• Mid-Maryland Ultra (Elkridge, MD) *Postponed until March 7, 2026*

Featured: Yukon Arctic Ultra (Whitehorse, YT)

The Yukon Arctic Ultra, widely regarded as the world’s coldest and toughest ultra, takes place February 1-13 in Canada’s Yukon Territory. The multi-day, expedition-style endurance event features three demanding distances (235k, 350k and 600k), with competitors traveling on foot, fat bike or skis. All races begin in Teslin and will follow the Yukon Quest dog sled trail, a route notorious for its isolation and brutal winter conditions. Race participants must be fully self-sufficient while battling temperatures that can drop as low as -40 degrees. In 2025, only six of the 46 starters reached the finish line. This year’s brave athletes have five days to complete the 235k, seven days to finish the 350k and 12 days to navigate the 600k. Read more about the 2026 Yukon Arctic Ultra here.

Other Canada or Mexico Events:

• Ultramarathon nonstop Cancún (Cancún, Mexico )

Email corys@ultrarunning with questions about adding your event to the UltraRunning Magazine calendar.