

RMRR Fall Marathon Training Series #2
Race Date
Sep 13, 2026
Location
Thornton, CO
Quick facts
- Date
- Sunday, September 13, 2026
- Location
- Thornton, Colorado
- Distance
- Half marathon (13.1 mi) + 30K
- Course
- Loop Course
- Terrain
- Road
- USATF certified
- Not listed
Highlights
Good For
Atmosphere
Course
The Experience
RMRR provides full and half marathon training opportunities for runners of all abilities. RMRR’s Marathon Training Series provides 10mi/20km and 20mi/30km races that are low cost, friendly, supported, and officially timed. 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.
Everyone is welcome to Marathon Training Series races: RMRR members, guests, training team members, everyone! The courses are well marked, with mile markers and aid stations. We’ll time your run, and winners of each distance will receive ribbons. We make it easy for you to work on your pace, nutrition, and hydration, and getting everything ready for your big race. 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 30 - 10mi & 20mi #2: Sep 13 - 20k & 30k #3: Sep 27 - 10mi & 20mi You are welcome to run 15mi, 25k, or another distance. Just let us know at the start. RMRR Members receive a 25% discount. Discount taken when you check out. Your membership must be current.
Logistics
Race Day
Sunday, September 13, 2026
Start Time
7:00 AM
Start Location
Riverdale Ballfields in Thornton, Thornton, CO, 80229
Course Info
Course Type
Loop Course
Terrain
road
Difficulty
Ultra-Flat
Net Drop/km
0 m (Flat)
Separation
0.0%
Also Offers
Quality Score
first year
no finisher counts yet
small race — neutral
needs a few years of results
3 timing sources
no finisher data yet
no winner time yet
typical high 86°F
Race Day Weather
5-year historical avgStart (Low)
56°
Afternoon (High)
86°
Hot conditions — adjust pace expectations, prioritize hydration
0.0"
Precipitation
12 mph
Wind
38%
Humidity
Frequently asked
When is the RMRR Fall Marathon Training Series #2?
The RMRR Fall Marathon Training Series #2 is held on Sunday, September 13, 2026, starting at 7:00 AM.
Where does the RMRR Fall Marathon Training Series #2 take place?
It takes place in Thornton, Colorado.
What distances does the RMRR Fall Marathon Training Series #2 offer?
The half marathon (13.1 miles), plus 30K.
Is the RMRR Fall Marathon Training Series #2 course flat and good for a PR?
The RMRR Fall Marathon Training Series #2 is a ultra-flat, loop course course.
HalfRuns editorial — independent, no paid placement.
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