Colfax Marathon
Denver, United States · May · Independent
Why people love it
- Half lap inside Empower Field at Mile High near mile 6 (10 km), then Sloan's Lake and Colfax Avenue.
- Strong crowds at the start, finish and the late Vine hill; firefighters hang medals.
- Since 2024 the marathon has its own lanes and Cherry Creek path apart from the half.
- Mostly flat apart from one long gradual climb, with views of the Rockies.
Watch out for
- Altitude of 1,609 m (5,280 ft) slows sea-level runners.
- Highs reached 28 °C (82 °F) in 2026 with little shade.
- Parking is confusing and the 2026 start was crowded.
- Gradual climb in miles 11 to 16 (18 to 26 km) and a late hill.
- Sold out for the first time in 2023; register early.
Race
How racers feel about it, how well it is run, and how it treats a first timer. Counts for 28% of the overall score.
Toughness: Tough
- Racer satisfactionLoved3.6
RaceRaves 3.9 from 33 ratings with several happy first-timers, but parking, a crowded finish and a thin-crowd 2018 report pull it down. · Medium confidence
- OrganizationWell run3.8
RaceRaves production 4.2, but mile markers 17, 20 and 23 were missing in 2022, parking is confusing and the 2026 start was crowded. · Medium confidence
- First timer friendlyDoable3.3
Mostly flat with big support and pace corrals, but altitude 1,609 m (5,280 ft), a 6:00 start and heat make it harder. · Low confidence
Course traits, not part of the score
- PR potentialAverage2.9
Altitude 1,609 m (5,280 ft) slows sea-level runners; FindMyMarathon 2025 shows 81 BQs, 3.6% of about 2,250 finishers. Flat otherwise. · Medium confidence
Course
Scenery, road surface, closures, and room to run. Counts for 20% of the overall score.
- Course sceneryBeautiful3.5
RaceRaves scenery 3.4: City Park, Cherry Creek, Mile High Stadium, Sloan's Lake and downtown with mountain views. West Colfax is plain. · Medium confidence
- Room to runSome pinch points3.4
Since 2024 the marathon has its own Cherry Creek path and lanes, but the 2026 start was crowded, and the zoo and river trail crowd. · Medium confidence
- Road surfaceGood3.6
Paved city streets and trails; no surface complaints found. · Low confidence
- Road closuresMostly closed3.5
Large city event with downtown and trail sections; closures were not confirmed by runners. · Low confidence
Course traits, not part of the score
- Course flatnessMostly flat3.6
Marathon gain is not published; the half had about 61 m (200 ft). Reviewers report a climb in miles 11 to 16 and a late hill. · Low confidence
- Net downhillEven3.0
Starts and finishes at City Park, net zero. A MarathonGuide tag says downhill but the loop makes that unlikely. · Medium confidence
Support
Crowds, aid stations, the start, and pacers. Counts for 20% of the overall score.
- Start logisticsSome waiting3.3
Corrals by goal time, but parking is confusing, the expo is far from the entrance and the 2026 start was crowded. · Medium confidence
- Pacers and timingGood3.5
Corrals by pace; pace group range unknown. · Low confidence
- Crowd supportStrong3.6
Strong at start, finish, fire station and the Vine hill, with performers in 2026; sparse in some stretches and 2018 was poor. · Medium confidence
- Aid stationsGood3.6
Stations every 3 to 5 km (2 to 3 mi) with water and Gatorade, gels at some. Finish food ran low for slower runners. · Medium confidence
Conditions
Air temperature, how predictable the weather is, setting, and spectating. Counts for 14% of the overall score.
- WindMostly calm3.8
A 2023 runner reported little morning wind. · Low confidence
- Air temperaturePleasant3.6
6:00 starts around 7 °C (45 °F), but highs up to 28 °C (82 °F) with little shade in 2024 and 2026. · Medium confidence
- Weather reliabilityVariable2.9
May ranges from 59 °F (15 °C) to 82 °F (28 °C) highs, drizzle in 2018 and heat in 2024; snow is possible. · Medium confidence
- Spectator friendlyEasy3.9
Loop with several viewing points and spectators can catch runners many times, per a 2023 runner. · Medium confidence
Course traits, not part of the score
- Low altitudeHigh altitude1.3
City Park sits near 1,609 m (5,280 ft), above the 1,500 m (4,900 ft) floor. · High confidence
Stay and travel
Hotels, walkability, getting there, and the town around the race. Counts for 10% of the overall score.
- Hotel availabilityGood3.8
Big city with many hotels, but book early for race weekend. · Low confidence
- Hotel valueNormal3.3
Denver in May is busy and no price evidence was found. · Low confidence
- WalkabilitySome driving3.0
Start at City Park is not walkable from downtown hotels per a 2018 reviewer. · Low confidence
- Travel easeEasy4.2
Denver International is a major hub. · Medium confidence
- LogisticsSome complexity3.1
Packets cannot be mailed, parking is confusing and the expo requires long walking. · Medium confidence
- Town and foodGood4.2
Denver has a strong food and brewery scene. · Low confidence
Entry
How hard it is to get a place, and what you get for the fee. Counts for 8% of the overall score.
- Getting inEasy3.5
Open entry but sold out for the first time in 2023, so register early. · Medium confidence
- Value for moneyGood value3.6
Medals frequently praised, shirt and expo merchandise mixed (swag 3.8). Fee not found. · Low confidence
Key facts
- Location
- Denver, Front Range, United States
- Typical month
- May
- Latest or next date
- 16 May 2027
- Organiser
- Independent
- Field size
- About 2,900 athletes
- First held
- 2007
- Distances
- 42.2 km (26.2 mi)
- Course type
- loop
- Start time
- 06:00
- Boston qualifier
- Yes
- Surface
- City streets, Cherry Creek and South Platte trails
- How to get in
- open
- Sells out
- Yes
- Air temperature
- 7–22 °C (45–72 °F)
- Humidity
- Low
- Altitude
- 1,609 m (5,280 ft)
- Nearest airport
- Denver International (DEN)
- Where to stay
- Downtown Denver, City Park area
- Booking
- Downtown hotels need a rideshare or long walk to City Park per a 2018 reviewer; book early.
What racers and reviewers say
- RaceRavesRaced 2022 to 2026 · aggregator · mixed-positive
Rated 3.9 from 33 runners (difficulty 2.9, scenery 3.4, production 4.2, swag 3.8). Reviewers agree on good production, strong support at the start and finish, gradual climb in miles 11 to 16 (18 to 26 km), an altitude effect and a parking mess.
“miles 11-16 are gradual uphill so save it for that point.”
- TeamRunRun (Lon Welsh), half marathonRaced 2023 · blog · Positive
Half marathon report: mostly flat with about 61 m (200 ft) gain, mountain views, firefighters and a big crowd at mile 10.5 hill, plentiful toilets, corrals by pace. Sea-level runners should bring sunscreen and extra water.
“If you want a flat, high altitude course, this is a great choice.”
- TeamRunRun (Jennifer S)Raced 2018 · blog · Mixed
Marathon report: flat course at about 1,500 m (5,000 ft), well-run, ample parking at City Park, aid every 2 to 3 mi (3 to 5 km). She found spectator turnout poor and the route skipped the best parts of the city.
“the best parts of the city are not necessarily on this course.”
- Denver Clarion (University of Denver) 2026Raced 2026 · article · Positive
On-course account: dawn crowds, performers, bagpipers at the fire station, a half lap inside Empower Field at about mile 6 (10 km), and a crowded start with the back of the field moving after 6:15.
- BibRave reviewsRaced various · aggregator · mixed-positive
A great city tour with strong residential crowd support, firefighters hanging medals, Sloan's Lake a highlight. Parking was the most common complaint, with a stadium expo requiring a lot of walking.
Raced Colfax Marathon? Your notes on the course, conditions and logistics help the next athlete decide.
Sources
Pages we used for facts and ratings. See how we rate.
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