WRC

RMRR Spring Marathon Training Series #1

location_on

calendar_today 29 Mar, 2026 – 11 Apr, 2026

directions_run Running

language Official Website

sell $20 – $55

About the Event

RMRR provides low-cost, low-keyed, supported, and timed training races for runners of all abilities. The races are planned to help you prepare for Boston, Colorado, Colfax, and other long spring races. We make it easy for you to work on your pace, your nutrition and drinking, and getting everything ready for your big race.

Sign up for one, or save money and choose the two race bundle. RMRR members get 50% off.

The races begin at 8am, at the Platte River Trailhead Park, at 88th and Colorado, in Thornton. The courses are out-n-back. so we can accommodate almost any distance between 10-20 miles.

Please note that for everyone's safety dogs or running strollers are not permitted on our courses.  Thanks for understanding.

Races Offered

10 Mile

Mar 29, 2026

straighten

Distance — 10 Miles

terrain

Type — Running

timer

08:00

sell

$20.00

2-Race Bundle Long - 20mi

Mar 29, 2026

straighten

Distance — 40 Miles

terrain

Type — Running

timer

08:00

sell

$55.00

20mi

Mar 29, 2026

straighten

Distance — 20 Miles

terrain

Type — Running

timer

08:00

sell

$30.00

Two-Race Bundle Short - 10mi

Mar 29, 2026

straighten

Distance — 20 Miles

terrain

Type — Running

timer

08:00

sell

$35.00

Weather Overview

These values represent the 3-year monthly averages for March in Thornton.

Temp (°C)
Feels Like (°C)
thermostat -2.5° / 12.4°
wb_sunny -7.2° / 8.0°
Wind (km/h)
Humidity (%)
air 10.3 /
water_drop 53.1%

About Thornton

Scenic view of

Thornton is a city of about 144,000 in the Denver Metropolitan Area of the western U.S. state of Colorado. The city lies northwest of Denver in Adams and Weld counties. It is a diverse community with a strong commitment to quality of life and environmental issues.

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