Sat, Jul 17, 2027

Summer Splash Prairie Dog Half, 10k, & 5k

Castle Rock, CO

Opens Jul 31, 2026Annual since at least 2014

Half Marathon10K5K

Entry is $25 now and rises to $35 after Aug 31, 2026, so registering before then saves $10.

About the Summer Splash Prairie Dog Half, 10k, & 5k

The course runs along East Plum Creek Trail on concrete the whole way, so it is smooth and consistent underfoot. There are real hills on the route, enough that the downhill stretches are genuinely tempting. Dogs on leashes and strollers are welcome, and the trail suits both.

The start and finish are at a high school, with parking at both the high school and the adjacent middle school. Advanced packet pickup happens the evening before at a local running shop in Castle Rock, with race-morning pickup available as well. Runners can enter a raffle by bringing donated food items for a local charity.

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Finish-Time Stats

Going by the 2025 results, this is a small, friendly field, with a competitive front end and a big recreational middle.

13.1 Miles · 2025 results

170finishers

1:20:26winner

2:12:34median

3:33:07cutoff

Top 3: Adam DeMaria (1:20:26) · Sean Keifner (1:27:19) · Spencer Stepp (1:28:16)

5K · 2025 results

136finishers

18:59winner

36:21median

1:10:10cutoff

Top 3: Chris McMahan (18:59) · Gavin Snyder (19:32) · Andrew Townsend (19:46)

10K · 2025 results

122finishers

34:58winner

1:06:34median

1:32:49cutoff

Top 3: EJ Rush (34:58) · Hunter Strand (34:59) · Nic Temple (35:42)

The Summer Splash Prairie Dog Half, 10k, & 5k has been held every year since at least 2014. That is as far back as RunSignup's records for this race go, so it may well be older.

Where Would You Finish?

Enter a finish time to see where it lands against the most recent 13.1 Miles results.

Median

See how your time stacks up nationally →

How we calculate these stats: RunSesh calculates these figures from the most recent published results of past editions, sourced from RunSignup. We show aggregates only: field size, winning and median times, and the cutoff. We never publish individual finisher tables. Last updated Jul 27, 2026.

Distances & Start Times

13.1 Miles7/17/2027 06:30$65

10K7/17/2027 07:00$35

5K7/17/2027 07:00$25

Going for a Time?

Set a goal and get a pace band: every mile split on a card sized for your phone lock screen, so race morning needs no math.

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Common Questions About the Summer Splash Prairie Dog Half, 10k, & 5k

Will I finish last at the Summer Splash Prairie Dog Half, 10k, & 5k?

Almost certainly not. Half the 13.1 Miles field finished slower than 2:12:34, and the last recorded finisher came in around 3:33:07, so there is a long tail of runners behind the middle of the pack. Most fields are far slower than people expect.

Is the Summer Splash Prairie Dog Half, 10k, & 5k a good first 13.1 Miles?

It is a small race (170 finishers), which is friendlier and less intimidating than a big-city event, though the field thins out. There is no qualifying time, and the finish-time spread above shows how varied the field really is. If it is your first 13.1 Miles, that spread matters more than the winner's time.

How competitive is the Summer Splash Prairie Dog Half, 10k, & 5k?

The 13.1 Miles winner ran 1:20:26 while the median finisher took 2:12:34. That spread points to a mixed field, with a competitive front and a big recreational middle.