Running Races in Thornton, Colorado 2026 | Browse All Races

There are 3 running races in Thornton, Colorado in 2026. The next is the I Ain't Scared (of 5k) on October 31. Distances include 5K races, ultras.

Sat, Oct 31 · Thornton, CO Thornton

Road 5k

From $29 Open Closing Soon

Sat, Dec 12 · Thornton, CO Thornton

Road 5k Run/Walk -TIMED and ScoredFun Run/Walk (Untimed, approx .75 miles)

From $16.5 Open

Sat, Jun 19 · Thornton, CO Thornton

Road 1/2 (ish) Mile Saunter - untimed1/2 (ish) Mile Saunter - untimed5k Run/Walk +1

From $16 Open

Running Races in Thornton, Colorado — 2026