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2027 Kaiser Permanente Colfax Marathon

The Kaiser Permanente Colfax half runs through a stadium, fire station, and the zoo.

Race Date

May 15, 2027

Location

Denver, CO

Standout80

Quick facts

Date
Saturday, May 15, 2027
Location
Denver, Colorado
Distance
Half marathon (13.1 mi)
Course
Loop Course
Terrain
Road
USATF certified
Not listed

Highlights

Good For

Destination Worthy

Atmosphere

Party FinishGreat Post Race

Course

Scenic Route

The Experience

On a May weekend in Denver, the Kaiser Permanente Colfax Marathon half-marathon draws nearly 6,000 runners from 46 states. Now in its 20th year, this urban course delivers one-of-a-kind sights: a mile through the Denver Zoo, a sprint through Empower Field at Mile High, and a pass by a working fire station, all linked by waterways and city streets. The atmosphere is electric, with spectators lining the route to cheer on the diverse field.

The half is fast and competitive—recent winning times hover around 63 minutes—yet welcoming enough to draw about a quarter of runners back each year. The finish line opens into a post-race party known for its charitable spirit, making the experience as rewarding off the course as on it. For a race that blends quirky landmarks with serious speed, Denver’s Colfax half is a standout destination event.

Race-provided description

The Kaiser Permanente Colfax Marathon is Denver's only marathon, held on a weekend in May. It features a Boston Qualifier marathon course that runs through Empower Field at Mile High, a fire station, and along waterways. The half marathon includes a mile through the Denver Zoo. Other events include an Urban 10 Miler, a 5K, and marathon relays. The race is known for its post-race party and charitable giving.

Logistics

Race Day

Saturday, May 15, 2027

Start Time

TBA

Start Location

Denver, CO

Directions

Course Info

Course Type

Loop Course

Terrain

road

Scenery

Urban, Lake River

Surface

Paved

Difficulty

Rolling Hills

Quality Score

Standout80
Methodology
Heritage20/20

19 years running

Size15/15

~5,890 finishers a year

Momentum5/5

growing or steady

Loyalty20/20

23% returning runners

Course & details3/15

2 timing sources

National draw10/10

runners from 46 states

Front-pack speed5/5

winner 1:03:05

Weather2/10

typical high 72°F

Race Day Weather

5-year historical avg

Start (Low)

44°

Afternoon (High)

72°

Warm — hydration strategy is key, start conservatively

0.1"

Precipitation

11 mph

Wind

54%

Humidity

Frequently asked

When is the 2027 Kaiser Permanente Colfax Marathon?

The 2027 Kaiser Permanente Colfax Marathon is held on Saturday, May 15, 2027.

Where does the 2027 Kaiser Permanente Colfax Marathon take place?

It takes place in Denver, Colorado.

What distances does the 2027 Kaiser Permanente Colfax Marathon offer?

The half marathon (13.1 miles).

Is the 2027 Kaiser Permanente Colfax Marathon course flat and good for a PR?

The 2027 Kaiser Permanente Colfax Marathon is a rolling hills, loop course course.

HalfRuns editorial — independent, no paid placement.

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