Grand Canyon Caverns, Show cave in Coconino County, Arizona

Grand Canyon Caverns is a dry limestone cave system on the Coconino Plateau in Coconino County, Arizona, 210 feet (64 m) below the surface. A 210-foot shaft blasted in 1962 holds a large elevator down to the passages. The natural entrance was sealed at Hualapai request. A dark brown plaque reading "SNOWBALL PALACE" sits on a pale, knobby rock face.

Walter Peck, a prospector searching for gold, came upon the caverns by chance in 1927 and opened them to travelers, charging 25 cents admission. In 1935 the Civilian Conservation Corps and the Works Progress Administration agreed with Peck to build a new entrance. A 210-foot shaft blasted into the limestone with a large elevator followed in 1962, when the natural entrance was sealed at the Hualapai Indians' request as a sacred burial place.

The caverns carry the Havasupai name Ŧathiil Ñwaʼa or Ŧathiil Ñhaʼa. Walter Peck first called them Yampai Caverns; the name became Coconino Caverns until 1957, Dinosaur Caverns until 1962, then Grand Canyon Caverns. The natural entrance was sealed at Hualapai request because it was a sacred burial place.

The main access is through an elevator that takes visitors directly into the main chamber, where paved walkways with handrails make movement easier. Additional tours go deeper into less developed areas and require a bit more mobility.

A cosmic ray telescope has been operating since 1979 about 38 meters (126 feet) below the surface, collecting scientific data on particle physics. The natural shielding provided by the rock makes the cave a suitable location for such measurements.