HalfRuns
RMRR Fall Marathon Training Series #2

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

Good Value

Atmosphere

Low Key

Course

Well Marked

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.

Course Info

Course Type

Loop Course

Terrain

road

Difficulty

Ultra-Flat

Net Drop/km

0 m (Flat)

Separation

0.0%

Also Offers

30K

Quality Score

Methodology
Heritage0/20

first year

Size0/15

no finisher counts yet

Momentum3/5

small race — neutral

Loyalty0/20

needs a few years of results

Course & details5/15

3 timing sources

National draw0/10

no finisher data yet

Front-pack speed0/5

no winner time yet

Weather0/10

typical high 86°F

Race Day Weather

5-year historical avg

Start (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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