Grand Canyon Caverns Inn: The Most Unique Overnight on Route 66
There are roadside attractions, and then there is the Grand Canyon Caverns Inn. Located along a remote and breathtakingly scenic stretch of Historic Route 66 between Seligman and Peach Springs in northwestern Arizona, this singular landmark offers something no other stop on the Mother Road can match: the opportunity to sleep in a hotel room 220 feet underground, inside a 65-million-year-old limestone cavern. Part kitschy Route 66 roadside attraction, part genuine geological wonder, and part Cold War relic, the Grand Canyon Caverns is one of those places that must be experienced to be believed.
Where is Grand Canyon Caverns Inn?
The Grand Canyon Caverns Inn is located at Mile Marker 115 on Historic Route 66, approximately 25 miles west of Seligman and 63 miles east of Kingman. The nearest Interstate 40 exits are at Seligman (Exit 123) or Peach Springs (Exit 71). The property sits at an elevation of about 5,400 feet on the Coconino Plateau, surrounded by the wide open high desert landscape of the Hualapai homeland.
Address: Mile Marker 115, Historic Route 66, Peach Springs, AZ 86434
Phone: (928) 422-3223
Hours: Tours typically 9:00 AM – 5:00 PM daily; check gccaverns.com for current schedule
The History of Grand Canyon Caverns
Discovery by Chance (1927)
The story of the Grand Canyon Caverns begins in 1927 with a woodcutter named Walter Peck — some accounts say he was actually on his way to a poker game — who was crossing the plateau when he nearly fell into a deep hole that heavy rain had recently widened in the limestone. The following day, Peck returned with local cowboys and descended into the cavern below. He found bones and shiny stones he believed contained gold; he purchased the property intending to mine it. When the assay came back showing worthless fool’s gold (pyrite), Peck pivoted to tourism instead. For just 25 cents, he began inviting visitors to explore what he called the Yampai Caverns.
The cavern passed through several owners and several names — Yampai Caverns, Coconino Caves, and eventually Dinosaur Caverns in the late 1950s — before landing on its current name, Grand Canyon Caverns, when a new owner installed an elevator shaft in 1962 and began developing the full visitor complex. The four-lane highway segment at the entrance, one of the only such widened sections between Williams and Seligman, testifies to the establishment’s prominence during Route 66’s golden era.
The Cold War Fallout Shelter
One of the most fascinating chapters in the Grand Canyon Caverns’ history came during the early 1960s. The cavern’s depth, dry conditions, and stable temperature — a constant 62°F year-round — made it an ideal fallout shelter during the height of the Cold War. In 1961, the complex was officially designated as a civil defense shelter, and during the Cuban Missile Crisis of 1962, the U.S. government stockpiled enough food and water rations in the cavern to support 2,000 people for up to two weeks. Remarkably, those original rations — still sealed and preserved by the dry air — remain in the cavern to this day and can be viewed by visitors on tours.
The Cavern Suite and Modern Era
The Grand Canyon Caverns Inn opened in 1963 to serve Route 66 motorists, and for decades it operated as a classic roadside attraction with motel rooms, a restaurant, gas station, and guided cavern tours. In 2012, the Cavern Suite debuted — a fully furnished hotel room 220 feet underground, inside the largest known chamber in the cave system. Marketed as the “oldest, darkest, deepest, quietest, and largest suite room in the world,” the underground room has no cell signal, no natural light, and a temperature that never deviates from 62°F. It has become one of the most sought-after unusual accommodations in the United States.
The caverns closed temporarily in 2022 following an elevator malfunction and underwent restoration under new ownership by the Havasupai Tribe. They reopened in June 2025 with guided cave tours, the underground Crystal Restaurant, and a refreshed visitor experience.
What to See and Do at Grand Canyon Caverns
Guided Cavern Tours
The primary attraction is the cavern itself — one of the largest dry caverns in the United States, with wide corridors, dramatic rock chambers, and geological formations that have been developing for tens of millions of years. Guided elevator tours descend about 200 feet below the surface and include stops at key chambers, explanations of the cavern’s geological history, and viewing of the original Cold War rations. Ghost walk tours and headlamp spelunking expeditions are also available for those seeking a more adventurous underground experience.
The Underground Cavern Suite
For the ultimate unusual overnight experience on Route 66, the Cavern Suite offers a fully furnished bedroom — complete with a king bed, living area, and bathroom — set 220 feet below the surface in the largest chamber in the cave system. The Crystal Restaurant, also located underground, serves meals in a 360-degree panoramic cavern setting. Both experiences require advance reservations and offer something genuinely unlike anything else on the Mother Road.
The Above-Ground Experience
The surface property is a delightful piece of Route 66 kitsch, with classic cars parked at the entrance, a retro-styled gas station (a nod to the Radiator Springs aesthetic from the Pixar film Cars, for which Peach Springs is sometimes cited as an inspiration), and giant dinosaur statues that recall the era when the caverns were marketed as “Dinosaur City.” The above-ground motel offers 48 standard rooms and RV hookups, and the outdoor pool and barbecue facilities make the complex a comfortable overnight stop in this remote corridor.
The Route 66 Setting
The Grand Canyon Caverns sits on one of the most intact and scenic stretches of original Route 66 in Arizona — a two-lane corridor through high desert plateau between Seligman and Peach Springs that offers an authentic feel of the Mother Road in its prime. The absence of development in either direction reinforces the sense of isolation and timelessness that makes this stretch so compelling for Route 66 enthusiasts.
Tips for Visiting Grand Canyon Caverns Inn
- Book the underground Cavern Suite and Crystal Restaurant well in advance — they are extremely popular and availability is limited.
- Check gccaverns.com before your visit to confirm current hours and tour availability, as the site has experienced periodic closures.
- Bring a jacket for cavern tours — the underground temperature is a constant 62°F regardless of surface conditions.
- The on-site gas station typically closes at 8 PM — fuel up before arriving if you’re coming in late.
- Cell coverage is spotty in this area — download offline maps before leaving Seligman or Kingman.
- Pair your visit with a drive through Peach Springs, where the Hualapai Lodge offers access to Diamond Creek Road and the Grand Canyon West Skywalk.
- The best time to visit is spring or fall — summer nights can be cool at this elevation but summer days are warm.
Final Thoughts on Grand Canyon Caverns Inn
The Grand Canyon Caverns Inn is the kind of place that defines what makes Route 66 special — genuine, eccentric, historically layered, and impossible to replicate. Whether you take the underground tour and marvel at the geological time capsule below your feet, sleep in a hotel room 22 stories underground, or simply stop to admire the dinosaur statues and retro gas station pumps, the Caverns deliver an experience that is entirely their own. It is one of the most memorable stops on all of Arizona’s Route 66.
Nearby Route 66 Highlights
- Seligman, Arizona — 25 miles east; birthplace of Route 66 preservation
- Hackberry General Store — 38 miles west
- Kingman, Arizona — 63 miles west
- Peach Springs — Hualapai Nation tribal seat, Diamond Creek Road, Grand Canyon West
