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| Event | Distance | When | Entry fee | Cap |
|---|---|---|---|---|
| Half Marathon | Half Marathon | Mar 21, 20279:00 AM | $70$80 after Dec 22, 2026 | – |
| 10K | 10K | Mar 21, 20279:30 AM | $50$60 after Dec 22, 2026 | – |
| 5K | 5K | Mar 21, 20279:40 AM | $40$50 after Dec 22, 2026 | – |
| VIRTUAL 10KVirtual | 10K | Mar 21, 20279:00 AM | $30$40 after Dec 22, 2026 | – |
| VIRTUAL 5KVirtual | 5K | Mar 21, 20279:00 AM | $25$35 after Dec 22, 2026 | – |
| VIRTUAL Half MarathonVirtual | Half Marathon | Mar 21, 20279:00 AM | $40$50 after Dec 22, 2026 | – |
Entry fees exclude processing fees. Prices and dates come from the race's registration page and refresh nightly.
The Half Marathon fee goes up to $80 on Dec 22, 2026.
Online registration closes Mar 21, 2027, unless the race fills first.
At $70, entry is about 17 percent above a typical half marathon in Colorado, which costs $60 right now.
A typical finisher at a half marathon in Colorado runs 2:12:38, about 10:07 a mile, based on 60 races with published results. Women typically finish in 2:19:55 and men in 2:03:31.
Sunrise on race morning is at about 7:05 AM, and the Half Marathon starts at 9:00 AM. The start sits about 7,980 feet above sea level, high enough that most runners from lower ground run noticeably slower.
Fees exclude processing fees. Comparisons use current entry fees and published results from races nearby.
19500 W 64th Pkwy, Golden, CO 80403
The pin marks the address the race lists, which is usually the start. Course maps are the organizers' own.
Aggregated from official results for All-Out Spring Fever. Individual finisher names are not stored here.
At the 2026 5K, the fastest tenth finished in 25:49 or better, the top quarter in 29:11, and half the field in 36:58; the last tenth came in after 55:07.
At the 2026 Half Marathon, the fastest tenth finished in 1:38:49 or better, the top quarter in 1:55:11, and half the field in 2:08:41; the last tenth came in after 2:46:29.
At the 2026 10K, the fastest tenth finished in 48:49 or better, the top quarter in 57:36, and half the field in 1:05:59; the last tenth came in after 1:27:32.
| Age | Women | Men |
|---|---|---|
| Under 20 | 55:04 | 22:28 |
| 20-29 | 28:14 | 23:09 |
| 30-39 | 25:59 | 24:10 |
| 40-49 | 26:43 | 23:14 |
| 50-59 | 32:22 | 27:42 |
| 60-69 | 35:09 | n/a |
| 70+ | 50:24 | 38:58 |
Groups with fewer than five finishers are left out. Awards vary by race; check the race's rules.
Where a finish time would have placed in 2026.
Up 40 percent since 2023.
All events combined, from official results.
From 2023 to 2026, the field went from 132 to 216 finishers, and the median time rose from 35:49 to 36:58.
| Year | Finishers | Median | Fastest tenth | Winner |
|---|---|---|---|---|
| 2026 | 216 (+65%) | 36:58 | under 25:49 | 20:12 |
| 2025 | 131 (+14%) | 36:40 | under 27:38 | 20:30 |
| 2024 | 115 (-13%) | 34:59 | under 25:02 | 18:18 |
| 2023 | 132 | 35:49 | under 26:58 | 20:48 |
From each year's official results for the 5K; virtual options are left out.
About average for Colorado 5Ks
The fastest quarter of the 2026 5K field finished under 29:11, against 29:37 in a typical Colorado 5K, so times here are about average.
Compares the fastest quarter of each field, so walkers and first-timers do not skew it. It reflects the course and the field together: a flat course, cool weather, or a competitive crowd all make times faster.
Around March 21 the day usually runs from 28°F at dawn to 53°F in the afternoon, with measurable rain on about 19% of days. Cold snaps dip to 16°F and hot years reach 76°F.
Based on 90 days within a week of the date over the last 5 years, from historical weather for the start area. Not a forecast.
What the organizers of All-Out Spring Fever cover on their registration page, in brief.
Schedule and packet pickup
Saturday, March 22. 12:30-3:30p Early packet pick-up & walk-up registration. Location: TBD. Sunday, March 23. 8:00a Packet pick-up and registration open. 8:50a Half marathon pick-up/registration close. 9:00a Half marathon start. 9:20a 10K…
Course
Jefferson County's NAAC Stadium. 19500 W 64th Pkwy, Golden, CO 80403. Wheelchair/Stroller Access: All are welcome, but there is one short (300') unpaved, gravel soft surface section of the course you should consider before registering…
Shirt and medal
♦ RRCA Certified Race Director— Organization you can count on! With hundreds of events under the belt of our director and a staff with 25+ years experience, your event will run smoothly. (Ha! No pun intended). ♦ Early AND Race Day Packet…
Organize this race? Add details or a correction
All-Out Multicourse is proud to host our 15th Annual Spring Fever, a rewarding event for both novice and experienced athletes set against the backdrop of Table Mountain and the stunning Colorado foothills. This spring celebration, featuring our mascot Buzzby, includes 5K, 10K, and half marathon courses that trace the scenic shores of Arvada's Blunn Reservoir via the Ralston Creek Trail. Conveniently accessible from nearby highways, Spring Fever is the endless series spring counterpart to Kooky-Spooky, and proudly benefits our NEW charity, People and Pollinators Action Network (we really love the bees). And don't miss that you can use Spring Fever to qualify for your BOLDERBoulder wave!