Mammoth Onyx Cave and Hidden River Cave in Kentucky Brochure 1930s

I picked up some old cave brochures recently.....  I am not sure exactly when this was printed, but most of the other items in the lot I found came from the mid 30s!  That seems about right for this one too.

I love this sort of thing, and I was thrilled to find promotional material on Hidden River Cave and Mammoth Onyx Cave dating back nine decades!