Come run Castle Rock's newest trail race at the beautiful Phillip S Miller Park! The event will offer five races: a 50k ultramarathon, a marathon, a half marathon, a 10K, a 5K and a family adventure race. The event will highlight the freshly cut, soft surface trails that are a part of the town?s largest ever park project. The race will begin near Castle Rock's state-of-the-art Miller Athletic Complex, a beautiful $30 million venue. The race course will showcase the newly constructed trails in Phillip S Miller Park and the single and double track trails at the adjacent Ridgeline Open Space. Don't forget to take in the impressive views of the surrounding buttes and the scenic views of Castle Rock as the trail twists and winds over the flowing race course. If you have any energy left after your race, you can climb Challenge Hill, a 200-step staircase on the hillside near the finish line.

Upcoming Races

Oct 2 2021
50 KM
The Castle Rock Trail Festival course is located entirely within the confines of Philip S Miller Park and Ridgeline Open Space in Castle Rock, CO. Starting near the amphitheater at PS Miller Park, the course travels along the yellow and purple trails before crossing a pedestrian bridge to the Ridgeline Open Space. Here, runners will circumnavigate the perimeter of the Rigeline Trail counterclockwise before returning to the pedestrian bridge. Once back in PS Miller Park, runners will continue on the yellow trail. Half Marathon, 10K and 5K runners will finish at the start line while 50K runners will get to experience the red and green trails within PS Miller Park. The 50K and marathon runners will then run a full second loop of the course. The entire course is run on entirely on dirt single and double track trails. The Ridgeline Trail 50K, Marathon, Half Marathon, 10K and the LiveBIG 5K are challenging courses with a lot of short ups and downs, twists and turns and some roots mixed in to test your ankles. There will be 11 aid stations in the 50K and marathon, six aid stations in the half marathon and two aid stations in the 10K. Each aid station will provide Gatorade, water and gels. 50K and marathon runners will also find a variety of food items, including pretzels, potato chips and fruit.
3,223 3,222 ft.
Multiple Loop Course
11 Aid Stations
8 :00 Cutoff
3 Elevation Rating
Hilly, ~2500-7500 feet in 50 miles
3 Surface Rating
Some rocks, root, and/or ruts


50 KM 50K View course top times

Date Finishers Top Result (M) Top Result (F)
10/03/20 32 4:43:42 5:26:47
10/05/19 50 4:11:41 4:44:22
10/06/18 56 4:17:48 4:44:24
10/07/17 38 3:57:15 5:44:39
10/09/16 55 3:58:22 4:58:09
We try to keep the most accurate information about this race, but changes do happen. Always visit the official race website for the most up to date information. If you see an error, please let us know

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