Date
Sat, 5 Dec 2026
Start
17:00
Venue
La Posta Quemada Ranch, Colossal Cave Mountain Park, Vail, Arizona
Vail, Pima County
Countdown
December
The half-marathon after dark. You run the north section of the 50-mile route out and back, on gentle terrain, with a head torch for company.
Key facts
014.5-hour cutoff
02Starts at 17:00, so expect to finish in the dark
Create a free training plan for the Colossal Vail 50/50 21 km
7-day free trial, no card required
The course
The route
Vail
Distance21km
Total climb289m
StartElevation
0 kmDrag map to rotate20.2 km
Weather
Early-December, Vail
19°CTypical high
4°CTypical low
-7°CColdest in 20 years
11%Days with rain
Highs around 19°C and lows around 4°C, but it has dropped to -7°C. Rain on 11% of days. Pack for the cold end, not the average.
NASA POWER data, 2006-2025, the week either side of race day
Results
Course verified. Results not yet available.
Organiser
Training
Training for the Colossal Vail 50/50 21 km
We don't do generic plans. We combine deep knowledge of this race's demands with your recent training, then build a plan with you that progresses as you do.
Beina integrates directly with your existing tools to understand your current fitness, and synchronise your planned sessions.
Intervals.icuWhat a Colossal Vail 50/50 21 km plan targets
Typical sessions
21 km with 289 m of climbing
Time on feet and fatigue resistance
Fuelling and pacing for the whole event
What your weeks look like
Typical sessions
Long runs that build time on your feet
Tempo and threshold sessions to hold race pace
Back-to-back weekend runs for fatigue resistance
Not a generic schedule
Typical sessions
Built from your current fitness and the time you actually have
Adapts every week as Beina learns how you respond
Syncs your sessions straight to Garmin and Wahoo
One clear next session, never a wall of spreadsheet
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Get your Colossal Vail 50/50 21 km plan.
7-day free trial, no card required.
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