Colossal Vail Participant Guide

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2025 PARTICIPANT GUIDE

presented by Fleet Feet Tucson

December 6, 2025

50M: 7:00 AM Start

55K: 7:15 AM Start

Half Marathon: 9:00 AM Start

Night Half Marathon: 5:00 PM Start

1. Welcome

Welcome to the 10th Colossal Vail 50/50 (CV50/50) presented by Fleet Feet Tucson. The Tucson metropolitan area is surrounded by mountain ranges and trail systems, more trails than any similar area in the continental U.S. Loosely organized trail runs in the area began in the late 1970s when Ken Young started the Arizona Mountain Runner series of events. At least one was long enough to qualify as an ultramarathon, and several took significantly longer than a road marathon. In the 1980s, a 50-mile event, the Old Pueblo 50 Mile Endurance Run, was organized in the Santa Rita Mountains south of Tucson. At about the same time, Dale Shewalter and others began to develop the Arizona Trail, traversing the state from Mexico to Utah. The 800-mile Arizona Trail was completed on December 16, 2011. It crosses the high desert to the southeast of Tucson and a bit east of the community of Vail, where it passes through Colossal Cave Mountain Park (CCMP).

In the spring of 2014, several local ultra runners came together to discuss the possibility of using that region and some portion of the Arizona Trail to create a new ultra event that would expose runners to the area and involve the local community. With the help of the Arizona Trail Association, Pima County Natural Resources Parks and Recreation, plus other interested organizations and volunteers, we designed the CV50/50 – an event for which all proceeds benefit the Arizona Trail Association. Our first eight years were a huge success and we’re truly excited you’ve decided to join us.

1.1 Sponsors and Volunteers

A lot of time and effort will go into creating an excellent race day. We wouldn’t be able to do it without the generosity of our sponsors and volunteers. These are wonderful people who are helping to make your race day successful. Please remember to thank them for their generosity and when possible, support our business partners.

2. The Course

The Arizona Trail is divided into Passages. The CV50/50 uses most of Passages 7 & 8, which link the Santa Rita Mountains south of the Tucson Basin to the Rincon Mountains on the east side of the Basin. While the course is relatively flat compared to our trails in the nearby mountains, the 55K still has a total of almost 2,300 feet of climb and the 50-mile has an additional 1,700. All is quite runnable, although some runners may find that walking the ascents, then running the downhills and flatter sections works best. There are some technical sections and rocky areas on all of the various distance courses, but generally the trails are quite forgiving and easy to navigate. Nearly the entirety of all distances take place on singletrack trails.

The CV50/50 starts and finishes at La Posta Quemada (LPQ) Ranch inside Colossal Cave Mountain Park (CCMP). It offers three distances and four events, a 50-mile, a 55k (~34 miles), a long half marathon during the day (~13.6 miles) heading south, and a night half marathon on the north section of the course. The 50M is a double out-and-back course: the first out-and-back heads south to the Peaks View (PV) aid station and back to La Posta Quemada. The 55K runners will run this stretch and call it a day. The second out-and-back heads north toward the boundary of the Saguaro National Park and is only for those who choose to run 50 miles or the night half marathon. Detailed course maps can be found on the website (https://runazt.org/colossal-vail-50-50/colossal-vail-course-info/).

2.1 Elevation Profiles

50 Mile – Approximately 4,000 Feet of Elevation Gain

55 K – Approximately 2,300 Feet of Elevation Gain

Half Marathon – Approximately 1,300 Feet of Elevation Gain

Night Half Marathon – Approximately 950 Feet of Elevation Gain

2.2 Course Markings

The CV50/50 course is almost entirely on the Arizona Trail. The singletrack will be obvious in almost all sections of the run. Both AZ Trail markers and a few rock cairns mark the trail. If you spot these markers, then you are on course. The race course will also be marked with orange flagging and the occasional orange pin flag attached to a wire shaft imprinted with the CV50/50 logo. Only the equestrian bypass section of the daytime half-marathon mile course will be marked with yellow flagging. 55K runners will never be on any part of the course marked with any color other than orange. The north section of the 50 mile course and entire night half marathon course will have orange reflective flagging for after dark. All intersections will be generously marked in both approach and depart directions. On long stretches between intersections “confidence” ribbons will be placed approximately every ½ to ¾ mile. Runners should see a ribbon every 10 to 15 minutes of running time. It is ultimately the responsibility of the runners to know the course, but generous course markings and AZT signage make this an easier course to navigate.

If you approach an intersection that has not been flagged as described, simply retrace your steps to the previous marked intersection.

3. Race Principles

It’s our desire for you to have a wonderful and successful race. Part of making that happen is ensuring that everyone is safe and operating under the same guidelines. The CV50/50 organizing committee has pared it down to these essentials:

Running is a celebration of life! Stay positive – be kind and encouraging to runners, volunteers, and crew.
Each runner’s official bib number must be worn prominently on the front of the body and must be easily visible at all times.
Littering is grounds for disqualification. Please respect the trail and all the others who enjoy its beauty. If you come across a piece of trash, do your part and pick it up. This won’t make or break your race, but it will make you a better person.
Be aware of other trail users on the Arizona Trail, including hikers, mountain bikers, and equestrians. The trail is open to all, and continued use of this National Scenic Trail is dependent on others having positive experiences during the race. Always yield to equestrians and be courteous to everyone you encounter along the way.
Music players & devices are NOT allowed, period. This includes any type of music device, earbuds, bone conduction headphones, or anything similar. The singletrack nature of this race, desert critters, out & back sections, and sharing the trail with others makes this a necessity.
The race director has the final say and decisions made are final.
Follow the marked course at all times. If you leave the course, you need to find your way back on foot to the point where you left the course and continue from there. Failure to return to the point where you left the course will result in disqualification or a time penalty at the discretion of the race director.
Runners are responsible for having a light source/headlamp and deciding when to begin carrying it for night running. We recommend erring on the side of caution and for 50 mile runners taking a light with you if you leave Pistol Hill (mile 40) at or after 3:15 pm. Nighttime half marathon runners must start the race with a light source. A seasoned ultra runner knows that nothing is entirely predictable. Remember that sunset is at 5:18 pm.
Ultra runners must check in AND out of every aid station.
All cutoff times will be strictly enforced. Runners must LEAVE an aid station BEFORE the cutoff time. This includes leaving after returning for any purpose.
Aid station captains have the authority to act on behalf of the CV50/50 run management.
Your participation in this race communicates consent to be pulled from the course for medical and/or safety reasons if it’s determined to be in your best interest.
Runners must personally notify an aid station captain and the radio communications staff at that aid station if you decide to drop. If you drop out without notifying an aid station captain and the radio operator, one of several entities could end up looking for you, possibly at your expense. Seeming to lose people, even if it turns out to be miscommunication, reflects poorly on the event and its chances of continuing.
Crew (friends, family, loved ones, members of your fan club, etc.) may access the Gabe Z (GZ) and Pistol Hill (PH) Aid Stations. Crew may NOT access the Sahuarita Road (SR) Aid Station, Peaks View (PV) Aid Station, La Selvilla (LAS) Aid Station, the north Turn-Around, or X-9 Ranch Road. One of these is directly off a major highway, one is on state trust land (permit required) with precarious access, and the other is a private road. Attempts to access any of these areas will result in the crew’s runner being disqualified. We’ve had several crews try to violate this rule in recent years, particularly at Sahuarita Road, and no leeway will be allowed on this fact as it can jeopardize the race permit.
Runners are responsible for the actions of their crew. Anyone participating in the race, whether a runner, crew member, or fan must comply with the Race Rules.

4. Cutoff times, Dropping Out, and Changing Distances

4.1 Cutoff Times

The 55K has one cutoff: Gabe Z (GZ) at mile 28.9 at 4:15 pm (9 hours). The 50-mile has a final race cutoff of 10:00 pm (15 hours) and three aid station cutoffs: The Gabe Z (GZ) Aid Station cutoff (mile 28.9) is 4:00 pm (9 hours), and the Pistol Hill (PH) Aid Station cutoff northbound (mile 39.1) is 7:00 pm (12 hours). In order to continue on, runners must exit the aid station before the cutoff time. Runners who return to an aid station after a cutoff are assumed to be forfeiting their race. There is no early start option.

4.2 Dropping Out

If you decide to drop from your race, an aid station captain must be informed of your name and bib number. Please remember this and communicate it to any person who might be crewing for you. If you leave without informing a captain, a lot of time and energy from many different entities could be required to track you down. Runners can drop at any aid station on the north leg of the course. Be aware that it might take a while, potentially hours, to return you to the Start/Finish if you drop.

4.3 Changing Distances

All 50 Mile runners will have the option to drop down to the 55 K during the event. Any runner who does so, however, will not be eligible for a top-three finisher award. If you decide to drop down to the shorter race, it is your responsibility to notify the finish line timer of the change. Any 50 Mile runner who finds themselves within 30 minutes of the generous Gabe Zimmerman (GZ) cutoff may want to strongly consider a drop down to 55 K.

5. Pacers

Pacers will not be allowed for any race distance. If you’d like to be accompanied by another runner, they must be a registered participant for the entirety of the race.

6. Drop Bags

Aid stations are very well-stocked, so please limit the size and contents of your drop bag. There are three drop bag locations in this race: Sahuarita Road (SR) at miles 11 and 23, La Selvilla (LAS) at miles 36 and 47 for 50 Mile runners only, and Pistol Hill (PH) at miles 39 and 44 for 50 Mile runners only. Please be sure to have your lights for night-time running ready in your La Selvilla (LAS) and/or Pistol Hill (PH) bags. Drop bags must be delivered to the designated area at the start/finish before the race by 6:50 a.m. Please be sure to clearly mark the bag with the location, LAS (La Selvilla), SR (Sahuarita Road), or PH (Pistol Hill), your bib number, and your name. This will help our aid station volunteers access your bag and assist you as efficiently as possible. When you’re done with your drop bag for the final time at an aid station, place it in the return to finish area so we can try to expedite your bag’s return. Your drop bags will be returned to the Start/Finish area where you’ll be able to pick them up later that day. Remaining drop bags will be available for pick up at Fleet Feet Tucson (7301 E. Tanque Verde Rd) Sunday, December 8th from 12:00 pm to 5:00 pm and Monday, December 9th from 12:00 pm to 6:00 pm. Unclaimed drop bags will be disposed of or donated.

7. Bib Numbers

Please wear your bib somewhere on the front of your body where the number will be clearly visible to event volunteers at all times and be ready to shout out your number as you enter and leave aid stations. We recommend wearing your bib on your shorts or pants in case you end up adding or shedding layers of clothing during the race.

8. Aid Stations

There are ten aid stations in the 50 Mile race, but because of the out-and-back nature of the course, four of the aid stations are accessed twice: Gabe Zimmerman (GZ), Sahuarita Road (SR), La Selvilla (LAS), and Pistol Hill (PH). Please note that crew access is not allowed at Sahuarita Road. You can find the details of each aid station listed in the tables below. All ultra runners must check in AND out of each aid station and please make sure the volunteer marked your number down. This is especially important when there are multiple runners approaching and/or leaving an aid station at the same time. The north-turn around may have emergency water, but please be sure to carry enough to get yourself from Pistol Hill (PH) to the turn-around and back. Portable toilets will be available at all aid stations EXCEPT for Peaks View (PV) and the north turn-around. Please use leave no trace principles if you need to go potty at a location other than a designated portable toilet.

This is a cupless race. If you would like to drink soda at aid stations, cups will be available for purchase at packet pickup, or you can bring your own. Runners are expected to carry bottles or hydration packs for water and Skratch Labs (electrolyte replacement drink). At a minimum, each aid station will have water, Skratch Labs, Coke, Mountain Dew, ginger ale, chips, pretzels, goldfish, potatoes with salt, M&Ms, cookies, bananas, watermelon, peanut butter & jelly sandwiches, bean wraps, and basic first aid supplies. If you feel that you need something specific that is not listed above, you should make arrangements with your crew or utilize your drop bags.

Half Marathon Aid Stations

Total Distance	Aid Station	Segment Distance	Crew Access	Drop Bags	Cutoff Times	Time Elapsed
0.0	Start	NA	Yes	Yes
4.9	Gabe Zimmerman (Heading South)	4.9	Yes	No
8.7	Gabe Zimmerman (Heading North)	3.8	Yes	No
13.6	Finish	4.9	Yes	Yes

55 K Aid Stations

Total Distance	Aid Station	Segment Distance	Crew Access	Drop Bags	Cutoff Times	Time Elapsed
0.0	Start	NA	Yes	Yes
4.9	Gabe Zimmerman (GZ) Southbound	4.9	Yes	No
11.0	Sahuarita Road (SR) Southbound	6.1	No	Yes
16.9	Peaks View (PV) South Turn-Around	5.9	No	No
22.8	Sahuarita Road (SR) Northbound	5.9	No	Yes
28.9	Gabe Zimmerman (GZ) Northbound	6.1	Yes	No	4:15 pm	9 hours
33.8	Finish	4.9	Yes	Yes

50 Mile Aid Stations

Total Distance	Aid Station	Segment Distance	Crew Access	Drop Bags	Cutoff Times	Time Elapsed
0.0	Start	NA	Yes	Yes
4.9	Gabe Zimmerman (GZ) Southbound	4.9	Yes	No
11.0	Sahuarita Road (SR) Southbound	6.1	No	Yes
16.9	Peaks View (PV) South Turn-Around	5.9	No	No
22.8	Sahuarita Road (SR) Northbound	5.9	No	Yes
28.9	Gabe Zimmerman (GZ) Northbound	6.1	Yes	No	4:00 pm	9 hours
35.5	La Selvilla (LAS) Northbound	6.6	No	Yes
39.1	Pistol Hill (PH) Northbound	3.6	Yes	Yes	7:00 pm	12 hours
41.7	North Turn-Around (no water)	2.6	No	No
44.3	Pistol Hill (PH) Southbound	2.6	Yes	Yes
47.9	La Selvilla (LAS) Southbound	3.6	No	Yes
50.1	Finish	2.2	Yes	Yes	10:00 pm	15 hours

Night Half Marathon Aid Stations

Total Distance	Aid Station	Segment Distance	Crew Access	Drop Bags	Cutoff Times	Time Elapsed
0.0	Start	NA	Yes	Yes
2.2	La Selvilla (Northbound)	2.2	No	No
5.8	Pistol Hill (PH) Northbound	3.6	Yes	No
6.55	Turn Around	0.75	No	No
7.3	Pistol Hill (PH) Southbound	0.75	Yes	No
10.9	La Selvilla (LAS) Southbound	3.6	No	No
13.1	Finish	2.2	Yes	Yes	10:00 pm	5 hours

9. The Environment

9.1 Critters

This run takes place in a biologically rich area. Cienega Creek and Davidson Canyon together, are a corridor between two sky island mountain ranges: the Rincon Mountains to the north and the Santa Rita Mountains to the south. Because of this, you could encounter any number of wild animals while on the CV50/50 course including javelina, skunks, rabbits, foxes, coyotes, deer, desert tortoises, snakes, quail, bees, black bears, coatimundi, badgers, mountain lions, 150 species of birds, 15 species of bats, and grazing cattle, to name a few. Most of these creatures pose little to no danger unless startled or threatened by a person. In addition, the foothills of the Santa Rita Mountains near Rosemont and the turnaround for the southern leg of this race, is an area where both jaguar and ocelot have been photographed.

Rattlesnakes: Pay attention to your surroundings and give any animals plenty of room to get out of your way, especially rattlesnakes. Rattlesnakes will not chase you and can only strike from a few feet away. They almost always warn you with a rattle, so give them room if you see or hear one.

Bees: Bees have been a problem in past years. They are attracted to the aid station food, and runners have even been stung. If you are allergic to bees, please carry medication, and if you are severely allergic, you may want to reconsider running this race. Individual foraging bees are not a problem, although they can sting you, but if you encounter a swarm or hive it’s important to get away as quickly as possible, hopefully in the direction of the finish line.

9.2 Weather

The average high in the Vail area on December 6th is 64 degrees. The average low is 40 degrees. Sunrise will be at 7:11 a.m. and sunset is at 5:18 p.m. Be sure to check the weather forecast in the days leading up the race so you can prepare accordingly. If there is a forecast of an unusual weather system coming through that day, you can expect an email from race management with additional instructions.

9.3 Green Things

Not only is this area an important corridor for animals, it has an outstanding variety of plant life. This is a transitional zone between the Sonoran and Chihuahuan Deserts, including numerous plant communities ranging from Saguaro-Palo Verde to Mesquite Grassland to Subtropical Riparian habitat along Cienega Creek. In this region there are plants that make their most northern appearance and others that make their most southern stand. Some notable plants that you will see on this run are saguaro, barrel cactus, ocotillo, agave, prickly pear cactus, yucca, mesquite, palo verde, creosote, and the endangered Red Pineapple cactus (look for these on both sides of the I-10 tunnel crossing). Many of these species have spines which are easily avoided by not running into the plants. If you do end up with spines stuck to you, aid station volunteers are prepared to help.

10. Crew/Spectators

Welcome to all crews! If you’re new to the ultra running world, you should know that the word “crew” encompasses family, friends, members of a runner’s fan club, etc. We’re happy to have you at the CV 50/50. You’re an important part of your runner’s experience. A list of crew-accessible aid stations is presented in the Aid Stations section of this guide. Here are some items we’d like you to keep in mind as you prepare and take care of your runner:

You can visit your runner at any of the crew-accessible aid stations and the start/finish line during the race, but nowhere else.
There is NO crew access at the Sahuarita Road (SR), Peaks View (PV) or La Selvilla (LAS) aid stations; or the North Turnaround. These locations are in high-traffic, difficult-to-access, permit-required areas. Please do not attempt to meet your runner at any of them. Failure to comply will result in your runner being disqualified.
There is no public access to X-9 Ranch Road near the Pistol Hill (PH) aid station. Please do not drive on this road under any circumstance. Failure to comply will result in your runner being disqualified from this race.
The aid station captains are in charge of how aid stations are run and what happens around them. Please comply with captain requests.
Aid station food and drink are meant for runners only. Please refrain from entering the aid station area unless you are accompanied by your runner.
The Pistol Hill (PH) aid station is located just off of Pistol Hill Road where runners will be crossing and friends and family will be waiting. Please drive with caution and be very careful crossing the road. There tends to be fast moving traffic on this road.
Please be courteous of others and use common sense when parking. We want this to be a positive experience for everyone involved, including those who live in Vail.
Please be aware and respectful of our race principles (listed in Section 3).

11. Directions

Directions to the Start/Finish Line in Colossal Cave Mountain Park’s La Posta Quemada Ranch

GPS Coordinates: 32.0505089, -110.6374164

Map search for “Boomerang Riding Adventures”

From I-10, take exit 279 and head east on Colossal Cave Road. Follow the signs to Colossal Cave Mountain Park. At the traffic light (Mary Ann Cleveland Way), turn right on Colossal Cave Road. After 2.2 miles, turn right on E Colossal Cave Road. Normally this road is closed to all traffic, but will be open for the CV 50/50.

If you’re traveling through Tucson, take Broadway east to Camino Seco and turn right (south). Turn left at the first light, Old Spanish Trail. You’ll stay on Old Spanish Trail until you reach Colossal Cave Mountain Park (about 17 miles) and follow signs to “Ranch” not the cave!

From Start/Finish to the Gabe Zimmerman (GZ) Aid Station

GPS Coordinates: 32.0139686, -110.6475833

Map search for Gabe Zimmerman Trailhead

After you exit Colossal Cave Mountain Park, take Old Spanish Trail about two miles and turn left on Pistol Hill Road/Colossal Cave Road (later in the 50 Mile event you will turn right on Pistol Hill to access that aid station). Stay on Colossal Cave Road about 7 miles and turn left on the Frontage Road/Old Benson Highway. After about 5 miles, Gabe Zimmerman Davidson Canyon Trailhead will be on your right.

From Gabe Zimmerman (GZ) Aid Station to Pistol Hill (PH) Aid Station

GPS Coordinates: 32.0909348, -110.6243218

Turn left onto the frontage road and stay on it until you reach Colossal Cave Road (It may be faster to access the freeway). Turn right on Colossal Cave Road (which eventually turns into Pistol Hill Road) and follow it until you reach Old Spanish Trail. Cross Old Spanish Trail (Pistol Hill becomes a dirt road here). Drive with caution. The aid station will be a few miles down the road on your right. Please drive past the aid station (past the cattle guard) and park in the small dirt parking lot on your right. If this area is full, please head back south on Pistol Hill Road and park carefully on the side of the road other cars are parked on. This is a narrow, very busy road. Please exercise caution when crossing the road.

From Pistol Hill (PH) Aid Station to the Finish

GPS Coordinates: 32.0505089, -110.6374164

Map search for “Boomerang Riding Adventures”

Take Pistol Hill south until you reach Old Spanish Trail. Turn left. Old Spanish Trail will lead you directly into the park. Once inside the park, follow signs to Ranch, not Cave.

12. Packet Pickup & 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 5th from 12:00 pm to 5:00 pm. Packet pickup will also be available at race headquarters beginning at 6:00 am on December 6th. All runners are required to check in on race day. Check in begins at 6:00 am.

13. Event Schedule

Friday, December 5th

12:00 to 5:00 pm: Packet pickup at Fleet Feet Sports (7301 E. Tanque Verde Road)

4:00 to 6:30 pm: Pasta Dinner at Charron Vineyard (18585 S. Sonoita Hwy) – advance tickets required

Saturday, December 6th at La Posta Quemada Ranch

6:00 am: Packet pickup, runner check in, and drop bag collection

6:50 am: Cutoff for 55 K and 50 Mile check in and drop bag collection

7:00 am: Start of 50 Mile race (there is no early start option)

7:15 am: Start of 55 K race

8:50 am: Cutoff for Half Marathon check in

9:00 am: Start of Half Marathon race

11:00 am: Food Service Begins for Runners (available for Purchase by Crew/Spectators)

12:00 pm – 3:00 pm: Live Music Entertainment by Jacob Acosta

4:00 pm: 50 Mile Cutoff at Gabe Zimmerman Trailhead aid station

4:15 pm: 55 K Cutoff at Gabe Zimmerman Trailhead aid station

4:50 pm: Cutoff for Night Half Marathon check in

5:00 pm: Start of Night Half Marathon

7:00 pm: Cutoff at Pistol Hill aid station for 50 Mile runners heading north (mile 40)

10:00 pm: Cutoff for 50 Mile finish & Night Half Marathon finish

Sunday, December 7th at Fleet Feet (7301 E. Tanque Verde Road)

12:00 to 5:00 pm: Drop bag pickup

Monday, December 8th at Fleet Feet (7301 E. Tanque Verde Road)

10:00 am to 6:00 pm: Drop bag pickup