Friday, May 26
Iron Horse Bicycle Classic. Watch or compete as bikers race the train to Silverton. 7 a.m. Durango to Silverton, ironhorsebicycleclassic.com. Through May 28.
Saturday, May 27
Gunnison Growler Weekend. 64- and 32-mile mountain bike rides and events throughout the weekend. Hartman Rocks Recreation Area, Gunnison, gunnisontrails.com. Through May 28.
Monday, May 29
BolderBoulder 10K. America’s favorite 10K race creates a full day of fun for all, from walkers to elite athletes. Races finish at CU’s Folsom Field. Pro Wheelchair wave kicks off at 6:50 a.m. with elite men’s race expected to finish at the stadium at 11:45 a.m. For information go to bolderboulder.com.
Vail Valor Races. Watch or participate in the full marathon, marathon relay, half marathon, 5-mile run/walk, or 1-mile family run. Vail, 970-445-7076.
Saturday, June 3
Buena Vista Bike Fest. Road rides of various distances including a century and metric century. 7 a.m. McPhelemy Park, Highway and Main Street, Buena Vista.
Burning Can Festival at Lyons Outdoor Games. Get your summer on with outdoor sport competitions complete with live music and beer from more than 50 breweries. Bohn Park, 219 Second Ave., Lyons, burningcan.com/lyons. Through June 4.
Fire Hydrant 5K and Pet Expo. Support the Larimer Humane Society with this dog-friendly 5K fun-run or walk. 8 a.m. The Promenade Shops at Centerra and Chapungu Sculpture Park, 5971 Sky Pond Drive, Loveland, 970-226-3647.
Longmont Triathlon Weekend. Kids-only and beginner triathlons on Saturday; Colorado’s longest running adult triathlon on Sunday. Centennial Pool, 1201 Alpine St., Longmont, 303-651-8406. Through June 4.
Palisade Gran Fondo. An epic group bike ride. The route will have something for everyone with its steep climbs and rolling hills, ﬂat sections and gorgeous scenery. 7 a.m. Peach Bowl Park, 600 Logan Ave. Palisade, palisadegranfondo.com.
Run the Rockies. Half-marathon starts at 8 a.m., road 10K starts at 8:30 a.m. Racers must take a shuttle bus from Frisco to the start of the race at Copper Mountain, as there is no racer parking available at start line. 800-424-1554.
Taste of Louisville 5K/12K. Run through Historic Main Street, Louisville, right through all the action of the Taste of Louisville, and continue on Louisville’s trails. Main Street and E. Lafayette Street, Louisville, tastehalf.com.
Sunday, June 4
Steamboat Marathon & Half Marathon. Run alongside the roaring Elk River and take in the mountain scenery. 7:30 a.m. Routt County Courthouse, 522 Lincoln Ave., Steamboat Springs, 970-879-0880, steamboatchamber.com.
Saturday, June 10
American Heart Association Heart Walk. Join thousands to walk for heart and stroke awareness. 5K and 1-mile distances. 7:30 a.m. Sports Authority Field at Mile High, 1701 Bryant St., Denver, 866-430-9255.
Ironkids Boulder Fun Run. An event for young ones to get in on the racing action with different distances depending on age. 8 a.m. Boulder High School, 1604 Arapahoe Ave., Boulder, ironman.com.
Sunday, June 11
Garden of the Gods 10-Mile Run. A physically demanding course through some iconic rock formations. Garden of the Gods, 1805 N. 30th St., Colorado Springs, gardentenmile.com.
Ironman Boulder. The classic endurance race in a triathlon mecca. 7 a.m. Boulder Reservoir, 5565 N. 51st St., Boulder, ironman.com.
REVEL Rockies Marathon and Half-Marathon. Whether you do half or all the way, it’s all downhill in this Evergreen to Morrison marathon. 6 a.m. Evergreen, runrevel.com/rdv.
Saturday, June 17
Big Gay 5K. Walk or run this 5K as part of Denver’s PrideFest in support of queer, open and equal rights. 10 a.m. Civic Center Park, E. Broadway Avenue and Colfax, Denver, glbtcolorado.org.
Estes Park Marathon. Offering full, half, team relay or 10K races. 6 a.m. The Dao House, 6120 Highway 7, Estes Park,
Bacon Burner 6K. A 3.8-mile out-and-back run on a paved trail with views of snow-capped peaks and Dillon Reservoir. 9:30 a.m. Frisco Marina, 267 Marina Road, Frisco,
G’Knight Ride. Come ride a cruiser bike on Longmont’s scenic greenways; there’s a kids’ festival and rides. 3 p.m. Roosevelt Park, 700 Longs Peak Ave., Longmont, 303-319-9882, gknightride.org.
Sunday, June 18
Bicycle Tour of Colorado. Take a six-day, 453-mile tour of the Centennial state on two wheels, beginning and ending in Pagosa Springs, bicycletourcolorado.com. Through June 24.
Father’s Day 5K. Celebrate Father’s Day by proving you can keep up with your kids in this 5K run or walk. 8:30 a.m. Mountain Avenue, Downtown Fort Collins, 970-221-6683.
Mount Evans Ascent Race. A foot race to the top of 14,264-foot Mount Evans. 6:30 a.m. Echo Lake, Highway 103, Idaho Springs, 303-642-7917.
Thursday, June 22
Crested Butte Bike Week. Experience the birthplace of mountain biking and ride singletrack at the oldest mountain bike festival in the world. Crested Butte, cbbikeweek.com. Through June 25.
Tuesday, July 4
Colorado Firecracker 4K/4 Mile. Run for it or don’t in a laid back atmosphere with super comfy event shirts and an amazing crawfish boil. Toast the U.S.A. with a free Pabst. 8 a.m. Erie Community Park, Erie, coloradofirecrackerrun.com.
Mount Evans Freedom Run 5K. Support Mount Evans Home Health & Hospice with a morning run. 8 a.m. Evergreen Middle School, 2059 Hiwan Drive, Evergreen, 303-674-6400.
Friday, July 7
Roger’s River Run 5K. Wear your glow-in-the-dark running gear for this night-time run before boogying down at the Rhythm on the River. 7:45 p.m. Roger’s Grove Park, Boston Street and Hover Street, Longmont, 303-776-6050.
Saturday, July 8
LG Triathlon and LG Kid’s Triathlon. A fun sprint triathlon for 6 to 13 year olds. 10 a.m. Eagle Pool and Ice Rink, 1700 Bull Pasture Road, Eagle, lgtri.com.
Triple Bypass Bicycle Tour. A 120-mile bike ride from Evergreen to Avon with more than 10,000 feet of elevation gain, with free bag drop in Loveland and special prizes. Go both ways to make it a double Triple Bypass! 7 a.m. Day 1 Start: Bergen Park, Evergreen, Day 1 Finish: Harry A. Nottingham Park, Avon, triplebypass.org. Through July 9.
Sunday, July 9
Boulder Peak Triathlon. One of the country’s longest and most well-known triathlons that attracts the pros with a $25,000 prize purse. Boulder Reservoir, 5565 N. 51st St., Boulder, 5430sports.com.
Steamboat Bike Week. Group road rides, downhill thrills, clinics that offer the chance to meet fellow cyclists and enjoy days spent in the Colorado sun. Various venues across Steamboat Springs, 970-879-0880, steamboatchamber.com. Through June 15.
Friday, July 14
Louisville Spaghetti Open Golf Tournament. Golf, golf, golf and, oh yeah, spaghetti! 7:30 a.m. Coal Creek Golf Course, 585 W. Dillon Road, Louisville, 303-666-5747.
Saturday, July 15
Aspen Valley Marathon. Three beautiful, scenic and mostly downhill runs along the Rio Grande Trail. Try to qualify for the Boston Marathon or try your feet at the half-marathon or 5K. Wagner Park, S. Mill Street, Aspen, Aspenvalleymarathon.com.
Bob Cook Mount Evans Memorial Hill Climb. An iconic bike race climbing 6,600 feet on the highest paved road in the U.S. 320 Chicago Creek Road, Idaho Springs, 303-249-6168, bicyclerace.com.
Frisco Triathlon. A different sort of triathlon with a 3K stand-up paddleboard, 15K mountain bike ride and 5K run on the trails. 8:30 a.m. Frisco Marina, 267 Marina Road, Frisco, 970-668-5276, ext. 3057.
Sunday, July 16
Barr Trail Mountain Race. 12.6 miles ascending from 3,500 feet in elevation and then 12.6 miles back again. 7 a.m. Pikes Peak Cog Railway, 515 Ruxton Ave., Manitou Springs, barrtrailmountainrace.com.
Friday, July 21
Black Diamond Open Golf Tournament. 18 holes of golf plus other competitions, a team contest and raffle prizes. 7:30 a.m. Indian Peaks Golf Course, 2300 Indian Peaks Trail, Lafayette, 303-666-9555.
Saturday, July 22
Courage Classic. Support the Colorado Children’s Hospital with a three-day cycling event starting and ending at Copper Mountain. Copper Mountain Resort, 209 10 Mile Circle, Frisco, childrenscoloradofoundation.org/ courage-classic. Through July 24.
Wednesday, July 26
Colorado Freeride Festival. Mountain bikers battle for more than $45,000 in prize money. Trestle Bike Park, Winter Park Resort, 85 Parsenn Road, Winter Park, coloradofreeridefestival.com. Through July 30.
Saturday, July 29
Enduro World Series Mountain Bike Race. See the only U.S. stop for the Enduro World Series. Various locations, Aspen/Snowmass, bigmountainenduro.com. Through July 30.
Saturday, August 5
AUDI Power of Four Trail Run and Mountain Bike Races. A 50K ultra trail-running race that covers all four area mountains and includes a 22K trail run and Vertical K race. 7 a.m. Base at Aspen Mountain, 601 E. Dean St., Aspen, 970-925-1220. Through August 6.
BEC Triathlon. 400-meter swim in the high altitude, open water of Nottingham Lake, 15K road bike heading back to Avon, and a 5K run through Nottingham Park. 8 a.m. Nottingham Park, 1 W. Benchmark Road, Avon, bectri.com.
Ironman 70.3 Boulder. 1.2-mile swim, 56-mile bike, and 13.1-mile run will offer 30 qualifying slots to the world championship. Boulder Reservoir, 5565 N. 51st St., Boulder, ironman.com.
LAPS Canine 4K. A charity fun-run for dogs, their owners and friends. 9:15 a.m. Frisco Historic Park Gazebo, 120 Main St., Frisco, 970-668-3230.
Littleton Twilight Criterium. A timed circuit bike race that’s just as fun for participants as it is for spectators. 3:30 p.m. Alamo Ave., Main Street, Downtown Littleton, littletonrocks.com.
Sunday, August 6
Lake Dillon Challenge Rowing Regatta. The highest and most scenic regatta in North America that celebrates the healthy recreational uses of the lake and environment with 2.5-mile or 6-mile courses. Frisco Bay Marina, 267 Marina Road, Frisco, 970-409-8435.
Saturday, August 12
Aspen Backcountry Marathon. This tough race, run on mountain dirt trails, is open to individuals and relay teams. 6 a.m. Rio Grande Park near downtown Aspen, aspenbackcountrymarathon.com.
Georgetown to Idaho Springs Half-Marathon. 8 a.m. Race starts next to Georgetown Lake in Georgetown, gtishalf.org.
Longmont Sunrise Stampede. A family-oriented 2-mile run/walk and 10K run on a certified course raising money for the St. Vrain Valley School district. 8 a.m. Silver Creek High School, 4901 Nelson Rd., Longmont, sunrisestampede.com.
Rocky Mountain Half Marathon. Part of the National Park Half Marathon Series, designed to leave you with the energy to enjoy the park. 6 a.m. Lake Estes Trail near Community Drive, Estes Park,
Tuesday, August 15
Transrockies Run. A stage race that takes you on an epic, 120-mile journey from Buena Vista to Beaver Creek over six days. 7 a.m. Buena Vista Heritage Museum, 506 E. Main St., Buena Vista, 866-373-3376. Through Aug. 20.
Saturday, August 19
Pikes Peak Ascent and Marathon. Two tough races only open to qualified runners. 7 a.m. Memorial Park, Manitou Springs, 719-473-2625, pikespeakmarathon.org. Through Aug. 20.
Sunday, August 20
Evergreen Kids Triathlon. Fun races of different lengths for 5 to 13 year olds. 9 a.m. Buchanan Park Recreation Center, 32003 Ellingwood Trail, Evergreen, 720-880-1100.
Sunday, August 27
Golden Gran Fondo Festival. Watch or participate in one the most challenging road races in the nation. 8 a.m. Parfet Park, 10th Street and Washington Avenue, 765-247-2453.
Saturday, September 2
Red Rocks Century. Ride in a full 100-mile century, 62-mile metric century or 33-mile Challenge ride to defeat ALS. Morrison, redrockscentury.com.