RMRR September 5k/10k
- Date
- September 13, 2026
- Distance
- 10k · 5k
From the Organizer
Rocky Mountain Road Runners holds a monthly Trophy Series in the Denver area. We provide a low-key, low-cost racing environment. Everyone is welcome to run with us!
The 10km race uses a handicap start system, slow-to-fast, spread over ~30 minutes. This gives everyone a chance to win. We'll use your estimated finish time to assign you a start time with others the same speed.
All 5k racers will start ~15min after the first 10km starters.
Race Day Details
Time: 10k starts at 8:00 am + your handicap.*
5k starts approximately 15min after the first 10k starter.
Show up 30 minutes early to get your tag and warm up.
Location: Riverdale Ballfields, 9830 Riverdale Road, Thornton, Colorado, 80229
Course: Both distances are out-and-back on a mix of paved and smooth gravel.
Parking: Plenty of parking at the park.
* The Trophy Series races use a unique, handicap start and scoring system. 10k racers start from slow to fast giving everyone a chance to win. When you register and pick up your number, we'll help you choose an appropriate start time that fits your estimated time.
Events
Weather
Typical Conditions
It's too far out for a forecast, so here's what weather on this date is normally like in the area. A race day forecast will replace this as race week approaches.
Typical High
83°
Typical Low
50°
Chance of Rain
20%
Based on US Climate Normals data from Northglenn, 3 mi from the venue.
Host City
About Thornton, CO
Population
142,878
as of 2023
Elevation
5,347 ft
Nearest Airport
DEN
Denver International Airport · 16 mi
Time Zone
Mountain Time
From Endurance Grid
A mid-size host city. Enough lodging and amenities to keep race weekend easy, without big-city sprawl.
Race Location
Your Next Start Line
What Are You
Waiting For?
Every finish line starts with a single decision. Claim your spot at RMRR September 5k/10k, put it on the calendar, and turn “someday” into a start date.
97
Days to train
- Race
- RMRR September 5k/10k
- Date
- September 13, 2026
Coming Up
More Running races near Thornton, CO
Treat Trot - Denver
Less than a mile away
Unicorn 5k (North)
5K
Less than a mile away
All-Out Dog Days
4 miles away
Summer Sizzler- Denver
Less than a mile away
From Endurance Grid
About This Sport
Endurance Grid is here to help you understand the sport, decide if it's the right fit, and learn how to prepare. For course distances, logistics, and race-day specifics, always defer to the race organizer's event page.
The 10K is the distance where running stops feeling like a starting point and starts feeling like a sport. Long enough to require a real training block. Short enough that race day is fully manageable for a first-timer who's put in the work.
Race day energy at a 10K is community at its best — strangers cheering you by name, people moving toward the same goal, an atmosphere that solo training can't replicate. It's fast enough that you'll spend the whole race pushing rather than managing your effort.
This is also the distance that builds the base for everything else. Most athletes who go on to run half marathons, do triathlons, or compete in HYROX started here. What you need: running shoes fitted to your stride, a training plan, and the race on your calendar. The registration is what makes the deadline real.
How long to train: 4–8 weeks for most fitness levels.
Running
From 5K to marathon, running races are the most accessible entry point into endurance sport. There's a distance for every fitness level and a community at every start line.
Frequently Asked Questions (FAQs)
- What is the RMRR September 5k/10k?
- RMRR September 5k/10k is a running race held in Thornton, Colorado on September 13, 2026. It is one of the many endurance events listed on Endurance Grid, a multi-sport endurance event calendar covering running races, triathlons, HYROX, and more endurance sports across the United States. Find more running races near you or explore our sports guides to learn what race day actually feels like.
- When and where is the RMRR September 5k/10k?
- Sunday, September 13, 2026 in Thornton, Colorado at 9830 Riverdale Road, Thornton, CO. Check the event page for exact start times and wave schedules.
- How do I register for the RMRR September 5k/10k?
- Registration is handled through the event's registration page. Confirm pricing and distances there, and sign up.
RMRR September 5k/10k
Sep 13, 2026