Running in Denver 2026 | Trails & Altitude Training

Running in Denver: Trails, Races, and Altitude Training

By Rick Janson | HGTV Host | Compass Luxury Realtor® | Updated May 4, 2026

Denver is one of the top running cities in the United States, offering more than 100 miles of paved off-street trails, 300 sunny days per year, and a nationally competitive race calendar. The city's 5,280-foot elevation makes every Denver run an altitude training session - conditioning that transfers directly to improved performance at sea level.

Cherry Creek TrailColfax MarathonAltitude TrainingWashington Park5,280 ft

What Are the Best Running Trails in Denver?

The Cherry Creek Trail is Denver's signature running corridor: 40 miles of paved, car-free pathway connecting downtown Denver to Cherry Creek State Park in Aurora, passing through Cherry Creek North, Glendale, and Englewood. The trail is flat, well-maintained, and open year-round, making it the most-used urban trail in Colorado.

The South Platte River Trail runs 14 miles through Denver's urban core, connecting to the Cherry Creek Trail at Confluence Park and extending north into Adams County. Washington Park's interior loop measures 2.6 miles - one of Denver's most beloved running settings, with the park's 165 acres providing a natural buffer from city traffic. The Highline Canal Trail extends 71 miles from the foothills near Waterton Canyon to Aurora, passing through Cherry Hills Village, Greenwood Village, and Centennial.

For trail runners seeking elevation gain, Red Rocks Park offers a 1.4-mile running loop around the amphitheater at 6,200 feet elevation. The Bear Creek Trail (9 miles, Jefferson County Open Space) connects Lair o' the Bear Park to Morrison through a scenic canyon.

How Does Denver's Altitude Affect Running Performance?

Running at Denver's 5,280-foot elevation means training with approximately 17 to 20 percent less oxygen than at sea level, depending on the individual's physiology and acclimatization status. Research published in the Journal of Applied Physiology indicates that altitude training at elevations above 5,000 feet increases erythropoietin (EPO) production and red blood cell mass - the same physiological adaptation elite athletes seek at altitude training camps in Park City, Utah (6,900 ft) and Flagstaff, Arizona (6,909 ft).

New Denver runners typically experience elevated heart rate, reduced pace, and faster breathing during the first 2 to 6 weeks of residence. Most runners are substantially acclimatized within 4 to 6 weeks. The adaptation benefit: runners who train in Denver and then compete at sea level often experience measurable improvements in aerobic performance because their bodies have adjusted to reduced oxygen availability.

Hydration is more critical at altitude. Denver's dry air (average relative humidity of 29%) accelerates fluid loss through respiration and perspiration. Running coaches in Denver recommend adding 20 to 32 additional ounces of water per hour of running compared to sea-level training recommendations.

What Major Races Are Held in Denver?

The Colfax Marathon (held annually in May) is Denver's largest road race weekend, drawing 28,000+ participants across a full marathon, half marathon, 10-mile, and relay divisions. The course runs along East Colfax Avenue - America's longest continuous commercial street - and through City Park, offering a uniquely Denver urban race experience.

The Cherry Creek Sneak (April) is a 4-mile road race in the Cherry Creek North neighborhood, held since 1986 and recognized as one of Colorado's most competitive short-distance road races. The Bolder Boulder (held in Boulder, 35 miles from Denver, Memorial Day Monday) is one of the largest 10K road races in the world with 50,000+ participants.

The Colorado Marathon (May, Fort Collins, 65 miles from Denver) offers a point-to-point course through the Cache La Poudre Canyon. Denver's winter racing calendar includes the Denver Turkey Trot (Thanksgiving) and the Frosty Foot 5K series. USA Track and Field (USATF) hosts regional cross-country and road race championships in the Denver metro annually.

"Washington Park at 6 AM on a Tuesday is one of the best-kept secrets in Denver real estate. Two-thirds of the people in that loop are neighbors - people who live within a half mile of the park. When I'm showing homes in Wash Park, I always tell buyers: the running community here is self-selecting for exactly the kind of neighbor you want."

Rick Janson | Compass Luxury Realtor® | HGTV Host | Author

Denver Running Trails and Routes: A Quick Reference

#	Trail / Route	Distance	Surface	Best For
1	Cherry Creek Trail	40 miles	Paved	Long runs, daily mileage, speed work
2	Washington Park Loop	2.6 miles	Paved	Interval training, social runs
3	South Platte River Trail	14 miles	Paved	Urban runs, access to city core
4	Highline Canal Trail	71 miles	Dirt/crushed gravel	Long distance, trail feel
5	Red Rocks Running Loop	1.4 miles	Paved, 868 steps	Hill training, altitude work
6	Bear Creek Trail	9 miles	Natural surface	Trail running, creek views
7	Sloan's Lake Loop	2.7 miles	Paved	Lake views, social running

Frequently Asked Questions

What is the best running trail in Denver?

The Cherry Creek Trail is the most popular and practical running trail in Denver: 40 miles of paved, car-free pathway connecting downtown to Cherry Creek State Park. The Washington Park interior loop (2.6 miles) is the most beloved neighborhood running setting. For trail runners, Red Rocks Park at 6,200 feet offers the most dramatic setting within 20 miles of the city.

How long does it take to adjust to running at Denver's altitude?

Most runners experience meaningful acclimatization to Denver's 5,280-foot elevation within 4 to 6 weeks of consistent training. Initial symptoms include elevated heart rate, slower pace, and increased breathlessness. Research suggests full aerobic adaptation can take 3 to 6 months. Hydration is critical - Denver's dry air accelerates fluid loss. Runners relocating from sea level should reduce training intensity by 10 to 15 percent in the first two weeks.

When is the Colfax Marathon?

The Colfax Marathon weekend is held annually in May, typically the third weekend of the month. The race weekend includes a full marathon, half marathon, 10-mile, and relay divisions. In 2025, the event drew more than 28,000 participants. Registration typically opens 8 to 10 months in advance and sells out for the full and half marathon distances.

Is Denver good for runners?

Yes. Denver consistently ranks among the top running cities in the United States. Factors include 300+ sunny days per year, more than 100 miles of off-street paved trails, a competitive road racing calendar year-round, and the altitude training benefit. Washington Park, Cherry Creek Trail, and the Highline Canal Trail serve different running styles and experience levels. The climate allows outdoor running in every month of the year.

What neighborhoods in Denver are best for runners?

Washington Park is the single best residential neighborhood for runners: the 165-acre park loop is 2.6 miles, the running community is large and active, and South Pearl Street dining is within walking distance post-run. Cherry Creek North provides direct trail access to the 40-mile Cherry Creek Trail. LoHi and Highlands connect to the South Platte and Cherry Creek trail system via the Highland Pedestrian Bridge. Platt Park connects to the Highline Canal Trail corridor.

Can you run at Red Rocks Amphitheatre?

Yes. Red Rocks Park is open for recreational use when no events are scheduled, which is most mornings. The 868-step stadium stair workout is one of the most famous fitness activities in Colorado. A 1.4-mile loop runs around the amphitheater perimeter. Red Rocks sits at 6,200 feet elevation - 920 feet above Denver - making it ideal for altitude interval training. Check the Red Rocks event calendar before visiting as stadium access is restricted on event days.

Does altitude in Denver make running harder?

Yes, initially. Denver's 5,280-foot elevation provides approximately 17 to 20 percent less oxygen than sea level, which directly affects aerobic capacity. Runners new to Denver typically see their easy-run heart rate increase by 10 to 20 beats per minute and their pace slow by 30 to 90 seconds per mile. After 4 to 6 weeks, acclimatization occurs and performance returns to near-sea-level equivalents. Many competitive runners view the altitude adaptation as a training benefit.

Are there running clubs in Denver?

Denver has a well-established running club ecosystem. The Denver Run Crew hosts free group runs from multiple locations. Fleet Feet Denver hosts weekly training runs from their stores in LoDo and Cherry Creek. Runners Edge is one of Colorado's oldest running specialty retailers with organized group runs. The Colorado Front Range Ultra Runners (CFRU) serves trail and ultramarathon runners. The Denver Track Club focuses on competitive road and track racing. Most clubs have beginner and advanced divisions.

Let's Talk Denver

Rick Janson is a Compass Luxury Realtor®, HGTV Host, and 4x published author with firsthand knowledge of every trail, club, dining district, and neighborhood in this guide. If these lifestyle priorities resonate, reach out and let's talk about which Denver neighborhood actually fits the way you want to live.

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