undergroundearth:
Mammoth Cave, Kentucky
undergroundearth:
Sand Cave - Where Floyd Collins died - mammoth Cave, KY
undergroundearth:
Sand Cave trail, Where Floyd Collins died - mammoth Cave, KY
undergroundearth:
Historic Entrance, Mammoth Cave, KY
undergroundearth:
gypsum flowers - Mammoth Cave, Kentucky
undergroundearth:
Inside Mammoth Cave, KY
undergroundearth:
Inside - Mammoth Cave, KY
undergroundearth:
Kentucky Monument, Mammoth Cave, KY
undergroundearth:
Floyd Collins Homestead - Mammoth Cave, KY
undergroundearth:
Gravesite of Floyd Collins -Mammoth Cave, KY
undergroundearth:
Historic Entrance, Mammoth Cave, KY
undergroundearth:
Carmichael Entrance, Mammoth Cave, KY
undergroundearth:
Kentucky Monument, Mammoth Cave
undergroundearth:
Crystal Cave - Mammoth Cave, KY - Floyd Collins Discovered
undergroundearth:
Crystal Cave - Mammoth Cave, KY - Floyd Collins discovered