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Ridgeline Trail 50K

  4.0 ( 1 ) Favorite


32.5 mile 52.2 kilometer out and back
96% Runnable


Ascent: 3,021' 921 m
Descent: -3,032' -924 m
High: 6,638' 2,023 m
Low: 6,393' 1,949 m


Avg Grade: 4% (2°)
Max Grade: 16% (9°)


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Trail shared by Derek Griffiths

The Ridgeline Trail 50K takes place in Castle Rock, CO.

Derek Griffiths

Features Fall Colors · Views


Come run Castle Rock's newest trail race at the beautiful Phillip S Miller Park! The event will offer three distances: a 50k ultramarathon, a half marathon, and a 12K (7.5 miles). The October 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 doubletrack 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.


The Ridgeline Trail Race 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 and 12K (7.5M) 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 runners will then run a full second loop of the course.

The entire course is run on dirt single and doubletrack trails. The Ridgeline Trail 50K, Half Marathon and 12K is a challenging course with nearly 3,500′ of climbing in the 50K, 1,400′ of elevation change in the half marathon and 800′ of elevation change in the 12K. There will be 11 aid stations in the 50K, six aid stations in the half marathon and two aid stations in the 12K. Each aid station will provide Gatorade, water and gels. 50K runners will also find a variety of food items, including pretzels, fruit strips, Kashi bars, and potato chips.

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Oct 6, 2018
Jacob Robison
Castle Rock sucks 32.5mi

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7 Views Last Month
2,214 Since Oct 21, 2016



Runners traverse the Yellow Loop during the Ridgeline Trail Races.
Oct 18, 2016 near Castle…, CO
Benches with great views along the trail
Sep 6, 2018 near Castle…, CO
Runners traverse the Yellow Loop during the Ridgeline Trail Races.
Oct 18, 2016 near Castle…, CO
Crisp winter day
Sep 6, 2018 near Castle…, CO
Lower portion of the Gold Loop.
Jul 1, 2016 near Castle…, CO
Section of the Gold Loop along the ridge.
Jul 1, 2016 near Castle…, CO

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