1966 advertising card for Crystal Cave in Kutztown, Pa.

This advertising card¹ from fifty years ago urges you to SEE INSIDE THE EARTH at Crystal Cave in Kutztown, Pennsylvania.

The natural attraction, which was "discovered" in 1871, was celebrating its 95th "anniversary" at the time (although, technically speaking, some of its rock formations and passages are more than 500,000 years old). The front of the card touts the joys of Crystal Cave as "An ideal vacation stop off — Entire cave well lighted — Paved walks and no hard climbing — Free Picnic Parks."

The back of the card is text-heavy and contains directions to Crystal Cavern, some history of the site and general information for visitors. It states that the cave is open from February 15 through December 1. Here in 2016, there are slightly fewer days of operation; it's open from a March 1 through November 30 (with special "ghost lantern" tours in October).

I'm guessing there are many, many folks in central and eastern Pennsylvania with fond memories of a trip to Crystal Cave. School field trip? Summer vacation? Share you memories in the comments section.

I've only ever been to one cavern in Pennsylvania — Indian Echo Caverns in Derry Township. I'd like to venture into more of them, with Crystal Cave and the water tour at Penn's Cave in Centre Country topping the list.² (You can't drive around central Pennsylvania without seeing the signs advertising Penn's Cave.)

Outside of Pennsylvania, I've been to the impressive Luray Caverns in Virginia³, but that's pretty much it. My Caverns Bucket List would include Mammoth Cave National Park⁴ in Kentucky and — OK, this is an extreme long shot and I'm probably not physically fit enough for it — the Sarawak Chamber in Malaysia.

Footnotes
1. The card is 6¼ inches by 3½ inches.
2. Check out Jim Cheney's Uncovering PA review of Penn's Cave.
3. My Papergreat to-do list includes a post a little collection I have of Luray Caverns ephemera from over the decades.
4. Mammoth Cave National Park inspired the pioneering 1970s text adventure Colossal Cave Adventure, which in turn inspired the likes of Zork and Mystery House.