Colossal Vail 50/50

Event details

The Colossal Vail 50/50 is a trail running event on portions of the Arizona Trail near Vail, Arizona, held at Colossal Cave Mountain Park. The event date is Saturday, December 6, 2025. Distances offered include:

• 50 Mile
• 55K
• 13 Miler (day)
• 13 Miler NIGHT

The race takes place on the ancestral lands of the Tohono O'odham. The Colossal Vail 50 Miler serves as the first leg of the Southern Arizona Triple 50. Awards are given to the top three male and female finishers in each event. Every ultra finisher receives an engraved railroad spike; half-marathon finishers receive a wooden finisher award. Discounted registration is available for Arizona Trail Association members, military veterans, Native Americans, and youth under 18. A registration discount is also available for runners who register for both the daytime and nighttime half-marathons.

Course, aid and logistics

Courses use recently completed sections of the Arizona Trail between Saguaro National Park-East and the foothills of the Santa Rita Mountains. The route features rolling high desert terrain, well-built trail, and wide vistas. The layout includes two out-and-back segments for the ultras; 50-mile runners may complete the 55K route and claim finisher credit if they do not complete the full 50 miles.

There are five aid stations along the routes; four of these are used twice. The event is a CUPLESS event; reusable cups are available for purchase or runners may bring their own. Skratch Labs is the official hydration sponsor. Camping and lodging options are available nearby. The event benefits the Arizona Trail Association. Refund policy: no refunds; cancellations made at least two weeks in advance receive a 75% credit transferable to another series event, cancellations within two weeks receive a 50% credit. Visit the organization's website for the most recent information.