Mystic Caverns

Mystic Caverns and Crystal Dome are show caves located between the cities of Jasper and Harrison, in the state of Arkansas, U.S., on the Arkansas Highway 7 Scenic Byway near the defunct amusement park Dogpatch USA. Sometimes called "the twin caves" because they are within 400 feet (120 m) of each other, the two caves maintain a year-round temperature of 58 °F, contain more formations per foot than any other caves in Arkansas, and are open for public tours year-round except during the January flooding season.

A third cave on the site, Not Much Sink cavern, has been deemed too dangerous to allow public tours.

Mystic Caverns, which has operated commercially since the late 1920s, is older than any other commercially operated cave in Arkansas, with the exception of Onyx Cave in Eureka Springs, and perhaps nearby Diamond Cave in Jasper, which has been toured since 1925. Crystal Dome was discovered in the mid-1960s during landscaping operations at Dogpatch USA. Great care was taken to preserve this pristine cave, and as a result 90% of it is still being formed. Tours began in the Crystal Dome in 1981.

The area was settled in the 1830s and named "Wilcockson". At that time the entrance to the as-yet-unnamed Mystic Caverns was a sinkhole which led to a 10-foot (3.0 m) drop into the cave itself. It is likely that settlers became aware of the cave and visited it prior to the 1850s. However, the first known visitor to the cave carved his name and the date on one of the formations:

Adam Kolbe
Wilcockson
April 16, 1919

The cave was first given the name "Mansion Cave", date unknown, for its huge open chambers, and around 1928 the first commercial tours were offered to the public. Owned by Jim and Bob Gurley, who constructed a wooden ladder down into the sinkhole and leveled the floor for trails, the tours were guided by the use of kerosene lanterns for illumination. They renamed the cave "Wild Horse Cavern" and stationed a hand carved horse next to the ticket booth.

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Wikipedia