Event details subject to change. Please confirm all information via event website.
Crimson Classic 5K
University of Denver - Carnegie Green Lawn 2150 East Evans Ave, Denver, CO, United StatesThe University of Denver's Annual Crimson Classic 5K Run/1.5 Mile Walk will take place on Carnegie Green Lawn. Music, stretching, and snacks will start at 2:15pm. The focus of the Crimson Classic is to celebrate wellness and to bring together our community. This is a free event! Please join us for a selection of wellness […]
Canyonlands Ultra
Behind the Rocks Trailhead Moab, UT, United StatesCanyonlands 100K, 50 Mile, 50K, Marathon, Half Marathon, and 15K Canyonlands Ultra starts and finishes at the Behind the Rocks Trail, along the border of the Behind the Rocks Wilderness Study Area. Moab's last hidden gem; its tall standing Navajo Sandstone domes and fins can be seen from many places along the course. From smooth double […]
Bridge Runner Ultra
Centennial Park - Cañon City Cañon City, CO, United StatesThis single loop 50k starts in the historic mining town of Canon City, Colorado. Runners' journeys will begin along the beautiful Arkansas River and travel through the historic granite blasted tunnels along Tunnel Drive. From here, runners will begin their steep climb to the highest point of the course at 7,109’ feet. At the top […]
Beware the Bear Trail Races
Bear Creek Lake Park 15600 W Morrison Rd, Lakewood, CO, United StatesRun the original Bear Creek Lake Park trail race - the Beware the Bear Trail Races - on October 17th. This trail race consists of a 14.2K or a 5K. Or do them both with the double! There is also a kids 1K.
Race to Cure Sarcoma 5K
Berkeley Lake Park 4601 W 46th Ave, Denver, CO, United StatesThe Race to Cure Sarcoma (RTCS) is the premier run/walk series in the United States, focused on raising awareness, providing education, and research funds for sarcoma. Each year, the Sarcoma Foundation of America (SFA) hosts more than (20) RTCS events across the country. We provide a unique space in the sarcoma community where patients, survivors, their friends, […]
Trick or Trot 5K
Apex Center 13150 W 72nd Ave, Arvada, CO, United StatesJoin the Apex Park and Recreation District Foundation for the inaugural Trick or Trot 5K! Runners and walkers of all ages and abilities are all welcome to join us for this Halloween celebration. Dress in your Halloween best for a chance to win prizes for the costume contest. There will be a separate 1-mile Trick […]
Foundry Halloween 5K
Soda Creek Elementary School 220 Park Avenue, Steamboat Springs, CO, United StatesA relatively new event to close out the Steamboat Springs Running Series season, bringing people of all ages together to celebrate Halloween in a safe, sober and fun way. The Foundry Treatment Center provides an opportunity for lasting recovery through an integrative body, mind and spirit treatment program. Comfortably located in the majestic Rocky Mountains […]
YMCA Creepy Crawl 5K
Palmer Lake Regional Park 199 County Line Road, Palmer Lake, CO, United StatesOur annual "spooky themed" race starts at the Palmer Lake Regional Recreation Area. We head down the scenic Santa Fe Trail for a bit then turnaround and finish with a lap around Palmer Lake. This is sure to be a fun day for everyone! Our Kids Monster Dash Fun Run is for kids 12 and […]
Eerie Erie 5K/10K
Erie United Methodist Church 604 Holbrook St, Erie, CO, United StatesThe world-famous Eerie Erie is a Halloween-themed 5k and 10k race that runs through historic downtown Erie and takes advantage of our beautiful trail system that weaves along the Coal Creek open space areas. The 10k passes by scenic Pleasant Hill Cemetery with panoramic views and where friendly spirits can’t wait to visit this year’s […]
MonsterDASH
Sloan's Lake Park 1700 Utica Street, Denver, CO, United StatesColorado's Favorite Halloween Runs....Each year the Theme Changes!! 2025 brings...SCARY CLOWNS / Circus Theme! Our best theme yet. Saturday Race is in Denver at 9:30am... then Sunday is in Louisville at 3:00pm on trails. This festival on Sloan's Lake, brings scary music, tons of Blow Ups, Carnival Games and Scary Clowns. The 5k and 10k […]
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