Summer Splash Prairie Dog Half Marathon, 10k and 5k

Lace up for the Summer Splash Prairie Dog Half Marathon, 10k, and 5k, a beloved annual event set against the picturesque backdrop of Castle Rock, Colorado, on Saturday, July 18, 2026. Part of the popular Prairie Dog Half race series, this event offers a fantastic summer running experience for all paces and abilities. The course unfolds along the scenic East Plum Creek Trail, presenting a 100% concrete surface perfect for a smooth stride. While the terrain includes some engaging hills, particularly in the initial and final miles, runners consistently describe it as a pleasant and manageable challenge, even at Castle Rock's elevation. Keep an eye out for the charming prairie dog town as you traverse the out-and-back route, where you'll be encouraged to stay to the right to accommodate fellow participants.

Runners can anticipate comprehensive support throughout their chosen distance. The Half Marathon boasts eight aid stations stocked with water and an electrolyte drink, plus energy gels at miles 5.5 and 6.5. The 10k offers four water stops, and the 5k provides two, ensuring hydration for everyone. Start and finish at Castle View High School, where you'll find ample parking, pre-race amenities, and a vibrant post-race celebration featuring finisher food, free photos, and age group awards. Typical race day conditions in mid-July include highs around 86°F and lows around 58°F, with only a 10% chance of precipitation, setting the stage for a warm but generally clear summer run.

Beyond the course, the Summer Splash Prairie Dog Half Marathon stands out for its inclusive atmosphere and generous offerings. This low-key yet well-organized race is both dog and stroller-friendly, allowing you to share the joy of running with your leashed canine companion or little ones in a stroller. All participants receive a gender-specific tech tee, a finisher's pint glass, and free photo downloads, with half marathoners earning an additional commemorative medal. The event also champions community spirit, partnering with local non-profits like Blessings in a Backpack; bringing five non-perishable pantry items can even enter you into a special raffle. With awesome volunteers and a focus on runner experience, this summer splash promises a memorable and rewarding day on the trails.