Dr. G. A. Thomas began showing Horse Cave (Hidden River Cave) around the turn of the 20th century.  In 1916, his son, Dr. Harry Thomas (pictured left) pioneered techniques for illuminating Kentucky caves by installing electric lights in Hidden River Cave, which he opened for tours.  Subsequently he opened Mammoth Onyx Cave (in 1921) with one tour and purchased Floyd Collins' Crystal Cave (in what is now Mammoth Cave National Park) where two tours were shown.  From 1927 until 1943, a total of five different tours, showing a variety of cave features unequalled anywhere, were available in the three caves.  His success was largely a factor of making the caves easily accessible.

Courtesy of: The Thomas Family

After Dr. Thomas' death in 1948, his wife Carrie (Steen) Thomas continued to operate Floyd Collins' Crystal Cave.  The management of the Thomas Caves then passed down to Dr. Thomas' daughter, Ruth (pictured below), and her husband Dr. E. R. Pohl.  Dr. Pohl was a geologist whose contributions to the origin, evolution and nature of the physiography and karst features were well known.

Dr. Thomas' grandson, Bill Austin, returned from college in the early 1950s and utilized his engineering skills to improve the lighting circuits in Mammoth Onyx Cave and to install Kentucky's first high-voltage cave lighting distribution system in Floyd Collins' Crystal Cave.

Bill Austin's legendary caving exploits were greatly influenced by Jim Dyer, manager of Floyd Collins' Crystal Cave.  Following in the footsteps of Floyd Collins, Jim Dyer's post-World War II cave exploration led the way to the discovery of many miles of passageways.

Both Dyer and Austin were pioneers in the field of 35mm U.S. cave photography.  Their beautiful photographs of Floyd Collins' Crystal Cave focused national attention on the cave.  As the size of the cave became known, a steady stream of volunteer explorers began studying the cave in the 1950s, leading to the creation of the Cave Research Foundation (CRF).

CRF explorations during the 1960s and 1970s led to connections between Floyd Collins' Crystal Cave and Mammoth Cave.  Those connections have since resulted in a cave system that is now the world's longest- more than 350 miles long.

Floyd Collins pictured right.