Onyx Mountain Caverns Features

One Acre Entrance Room used for shelter by Historic Indian Tribes thousands of years ago.

Many artifacts on display. (found deep in the ashes from their campfires)

Underground River. (the end has yet to be found)

Beautiful Onyx formation 35 feet high. Flowstone draperies, stalagmites and stalactites.

Columns & soda straws are seen throughout the tour.

The Onyx Mountain Caverns are located 12 miles west of Rolla, Missouri on Interstate 44, at the 169-J exit go east on the outer road 1 mile. 

Group Rate's Available

573-762-3341   or   573-762-2449

 This huge cavern has many natural scenic wonders and historical points not seen in other caves in the area.

History

In the scenic Gasconade River Valley of Pulaski County there is a large cavern known today as Onyx Mountain Caverns. The unique cavern has many formations, natural scenic wonders and a history not found in other caves in the area. The Woodland Indians used the cavern for shelter. Flint artifacts found indicate the cavern was used as a ceremonial cavern as well as evidence of residential habitation. The huge entrance to the cavern spans 400 foot long, 100 foot wide and 40 foot high, about I acre in size, and could have accommodated many small tribes of the area. By the time the first settlers came, the Woodland Indians had vanished. The Indians probably joined with the Osage tribes, or could some other fate have befell them? During the Queen Victoria Period of the 1800's several carloads of the beautiful Onyx of the cave were removed by the Imperial Onyx Company and shipped to St. Louis to be used in Victorian-style homes of that period and public buildings for decorative stone. An underground river runs through the cave, and bear  beds, where bears spent their winter hibernation,  are also found in one section.

Some prehistoric bones have been uncovered in the cavern's clay deposits and a few embedded within the onyx formations. Geologists and scientists have studied the cavern for years, the most recent being life scientists from Edward's University in Illinois. A rare algae has been discovered in the cavern, not found anywhere else in the world. The discovery is listed in the National Sciences Annual.  Although it never came to pass, plans were to use the cavern for a tuberculosis hospital in the late 1800's  and a Jet propulsion lab for testing Jet engines for military fighter planes in the 1950's. At the turn of the century, tourists coming from St. Louis on the Frisco railroad were brought up river from Jerome to see the large entrance room of the cavern.

The cave was opened in August of 1990. Guided tours for tourists, and educational tours for school field trips are available 7 days a week. The cave offers Native American Indian culture for school children. The cave was used as a shelter for about 10,000 years and has many unusual features, including a rare cave algae and unique box work formations. On the adjoining National Forest is the largest sink hole in the state. It is a canyon type sink, running 1/4 mile wide.with a 7 acre floor, this is a very unusual geological feature visited by thousands.