RMRR Fall Marathon Training Series #3
- Date
- September 27, 2026
- Distance
- 10 Mile · Other
- Price
- $20–$30
From the Organizer
RMRRs Marathon Training Series (MTS) races are low cost, friendly, supported, accurately measured, well marked, and timed. Each MTS has 10mi & 20mi, or 20k & 30k options. All you need to do is focus on your running!
The MTS fits well into training schedules for Colorado Springs, Boulderthon, Long View, Chicago, Monumental (Indy), New York, and other fall full and half marathons.
MTS#3 offers 10mi & 20mi options (we can accommodate almost any distance in between).
Please note that for everyone's safety, dogs or running strollers are not permitted on our courses. Thanks for understanding.
The races begin at 7 am at Riverdale Ballfields at 9830 Riverdale Road in Thornton Colorado.
#1: Aug 25 - 10mi & 20mi
#2: Sep 8 - 20k & 30k
#3: Sep 22 - 10mi & 20mi
RMRR Members receive a $5 discount off individual races and $15 off the 3-race bundles. Discount taken when you check out. Your membership must be current.
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
76°
Typical Low
44°
Chance of Rain
19%
Based on US Climate Normals data from Northglenn, 5 mi from the venue.
Host City
About Thornton, CO
Population
142,878
as of 2023
City 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.
Your Next Start Line
What Are You
Waiting For?
Every finish line starts with a single decision. Claim your spot at RMRR Fall Marathon Training Series #3, put it on the calendar, and turn “someday” into a start date.
102
Days to train
- Race
- RMRR Fall Marathon Training Series #3
- Date
- September 27, 2026
Coming Up
More Running races near Thornton, CO
Unicorn 5k (North)
1K · 5K · From $24 · E 108th Ave & Colorado Blvd
2 miles away
Summer Sizzler- Denver
1 Mile · 5K · 10K · Other · From $17 · Carpenter Park/Thornton Recreation Center Park
3 miles away
RMRR Fall Marathon Training Series
10 Mile · Other · From $20 · Riverdale Ballfields in Thornton
Less than a mile away
RMRR Fall Marathon Training Series #2
Other · From $20 · Riverdale Ballfields in Thornton
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.
With running, there's a distance for every fitness level, a community at every start line, and nothing beats the feeling of crossing a finish line you trained for.
Running is an endurance sport that rewards consistency, and showing up every week compounds in ways that will surprise you.
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 Fall Marathon Training Series #3?
- RMRR Fall Marathon Training Series #3 is a running race held in Thornton, Colorado on September 27, 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 Fall Marathon Training Series #3?
- Sunday, September 27, 2026 in Thornton, Colorado at Riverdale Ballfields in Thornton. Check the event page for exact start times and wave schedules.
- How do I register for the RMRR Fall Marathon Training Series #3?
- Registration is handled through the event's registration page. Confirm pricing and distances there, and sign up.
RMRR Fall Marathon Training Series #3
Sep 27, 2026