Just the Facts

Check Back for Updates

The Colossal Vail 50/50 (CV 50/50) presented by Fleet Feet Sports-Tucson website will continue to be updated regularly. Please check back for the most current information.


Click here to register!

13 mile fee schedule: $60 until Sept. 11 / $70 until Oct. 9 / $85 after Oct. 9

55k fee schedule: $90 until Sept. 11 / $100 until Oct. 9 / $115 after Oct. 9

50 mile fee schedule: $100 until Sept. 11 / $110 until Oct. 9 / $125 after Oct. 9

Date & Time

The 8th CV 50/50 will take place on Saturday, December 11, 2021. Three distances are offered: the 50-mile begins at 7 a.m. The 55K begins at 7:15 a.m. The Half-Marathon begins at 9 a.m. Depending on COVID protocols from Pima County, wave starts of 20 runners may be implemented.


Race day headquarters is at Colossal Cave Mountain Park’s La Posta Quemada Ranch in Vail, Arizona.

Packet Pickup and Check-In

Packet pickup will be held at Fleet Feet Sports located at 7301 E. Tanque Verde Road (520-886-7800) in Tucson on Friday, December 10 from 12:00 p.m. to 5:00 p.m. and on December 11 at the start/finish line. All runners are required to check in on race day. Check-in and packet pickup begin at 6 a.m.

Course Summary

The CV50/50 is comprised of two out-and-back segments on the Arizona Trail. The course begins by heading 16.9 miles south from La Posta Quemada Ranch at Colossal Cave. 55K runners return to the ranch for a finishing distance of almost 34 miles! The 50-mile racers continue past La Posta Quemada to the northern stretch of the course and cover 8 additional miles. Half-marathoners run south on the Arizona Trail for almost 6 miles, then a short segment of dirt roads and and sandy arroyos before returning to the trail and running north back to the finish line. The race concludes at La Posta Quemada where food, festivities, music and beer await.

Race Details

We will post updates periodically. To view the aid stations, segment mileage, crew instructions, and course rules, check out the Participant Guide and our Aid Station page. All aid stations will be fully stocked with a minimum of water, soft drinks, electrolyte replacement drink (Tailwind Nutrition), sweet and salty foods, and sandwiches. If a runner needs something specific during the race (i.e. gels, special foods, etc.), he or she will need to carry it or utilize crew and drop bags.

Course Information

This course consists mostly of rolling hills and beautiful open desert with moderate climbs and fast singletrack. This is a great course for fast times or stepping up from road marathons to the world of ultrarunning.

Time Limits

The 50-mile event has a time limit of 15 hours (10 p.m.).

The 55K has a final aid station cutoff (Gabe Z at mile 30) of 8.5 hours (3:15 p.m.).

The Half-Marathon does not have a time limit.


Pacers will not be allowed unless they are registered participants.


The average high in the Vail area on December 11 is 63 degrees. The average low is 42 degrees. Sunrise will be at 7:13 a.m. and sunset is at 5:19 p.m. Be sure to check the weather forecast in the days leading up the race so you can dress and prepare accordingly.

Forecast for Vail, Arizona


If you have any questions, feel free to contact us at matthew@aztrail.org.