Colossal Cave has captivated people for over a thousand years — and the park that surrounds it today preserves that full human history in one of southern Arizona's most richly layered landscapes.

Located at the southeast end of the Rincon Valley in Vail, Arizona, Colossal Cave Mountain Park encompasses 2,400 acres of geological features, riparian areas, canyon terrain, and views of the Rincon Mountains. The Arizona National Scenic Trail crosses the park. It is listed on the National Register of Historic Places.

The Cave

Colossal Cave is one of the largest dry caves in North America — formed from limestone and granite, and dry meaning it is no longer an active cave with growing formations but rather a stabilized geological marvel. What formations exist stopped growing thousands of years ago when the water table dropped and the cave dried out. What remains are stalactites, stalagmites, flowstone, boxwork, and helictites — frozen in time and illuminated on guided tours that last approximately 50 minutes.

The cave's history reads like a layered archaeological site. The Hohokam used it for shelter, storage, and as a shrine as early as 900 AD, forming a thriving farming community in the surrounding valley. Over the following centuries other Indigenous peoples came and went. In 1879 a rancher rediscovered the cave. In the late 1800s train robbers used it as a hideout following a robbery — a piece of Wild West history that is well documented and part of the cave's interpretive narrative. In 1905 a tunnel was excavated to mine bat guano, a valuable fertilizer commodity. During the Great Depression, the Civilian Conservation Corps constructed the handsome dressed-limestone headquarters buildings, and built the walkways, handrails, and lighting inside the cave. The CCC's work here is among the finest examples of their craftsmanship in Arizona.

Cave Tours (2026)

Three tour options are available:

• Classic Tour — approximately one hour, the standard guided cave experience covering history, geology, legends, and formations. The most accessible option for families.

• Lights Out Tour — experience the cave by lantern light, the same way early visitors did. A completely different atmosphere from the lit tour.

• Ladder Tour — 90 minutes featuring historic CCC ladders and hidden passageways for those wanting a more adventurous underground experience. Ages 12 and older.

• Wild Cave Tour — a full backcountry caving experience for ages 12 and older. The most immersive and physically demanding option.

Children under 5 are not permitted on cave tours.

La Posta Quemada Ranch

The ranch headquarters at the park is a 120-year-old working ranch that serves as a historical museum and research library. Exhibits explain the human and natural history of Colossal Cave Mountain Park and the Cienega Corridor. A gem sluice allows visitors to pan for gemstones. Trail rides follow the old National Mail Stagecoach route through the park's terrain. The open-air Terrace Café serves snacks and prickly pear treats. Gift shops at both the cave and the ranch carry gems, fossils, minerals, and Southwest-inspired souvenirs.

Hiking and Trails

Free hiking and biking trails wind through the park's terrain — from steep-walled canyons to riparian areas. The Arizona National Scenic Trail passes through the park, making it a trail town access point for long-distance hikers on the AZT. Interpretive loop trails connect key features of the park. The terrain transitions from desert scrub through canyon bottom riparian vegetation — birding is excellent throughout.

Camping — Posta Quemada Canyon (2026)

The campground sits tucked among saguaro cacti and mesquite trees in Posta Quemada Canyon — an area developed in 1934 by the Civilian Conservation Corps. Two main camping areas, El Bosquecito and La Selvilla, plus several smaller areas totaling 30 individual sites. Both main areas have water and restrooms.

Camping rates: $15/night per tent or per vehicle (RV, car, horse trailer). First-come first-served — no reservations. Check in and pay at the Cave Shop before entering the camping area. Front gates are locked at night — check park hours before arrival.

Quiet hours 10 PM to 6 AM. No generators, music, or loud noise during quiet hours. Fires permitted in barbecues and established fire rings when conditions allow — signs posted when fires are prohibited. Bring your own firewood or charcoal — cutting trees or branches in the park is strictly prohibited. Pets welcome on leash at all times.

An emergency 911 phone is located in the campground near the Y intersection where the road branches to El Bosquecito and La Selvilla.