Cave with Ice Age fossils opening in Indiana

A cave littered with the bones of Ice Age creatures will open for the first time to the public on Saturday.

As with many so-called "show caves," Indiana Caverns has the requisite geological formations and a river for subterranean boat rides. But the pre-historic bones — believed to be among the largest cache discovered in one cave — are the "frosting on the cake," says marketing manager Carol Groves.

Located in southern Indiana about 25 miles west of Louisville, the new attraction is part of the 36-mile-long cave Binkley cave system (the nation's 11th longest). Portions have been explored for more than half a century, but the section opening Saturday was only discovered three years ago by a group of caving enthusiasts.

Corydon cave jumps in size and national rank with passageway discovery

Nick Benton, lower left, and Indiana Speleological Survey
Vice President Rand Heazlitt explore the Davidson cave
passage in Harrison County last month.

For decades, explorers crawling through the vast limestone caverns beneath Corydon, Ind., hit dead ends when trying to connect two well-known caves.

But earlier this year, they had a breakthrough — finding a passageway linking Binkley Cave and Blowing Hole Cave, a spectacular uncharted section with tall cathedral-like caverns and an array of limestone formations.

The cool factor multiplied when the cavers with the Indiana Speleological Survey realized that by adding the seven-mile Blowing Hole Cave to Binkley, they'd unearthed a combined cavern that is now the 11th longest nationally, at nearly 35 miles.

That's big in caving circles, said Arthur Palmer, a retired hydrology professor at the State University of New York who explored Binkley in the 1960s with an Indiana University team.

"People all over are interested in what's happening at Binkley," Palmer said, because "it's kind of rare for a cave to undergo a big (growth) spurt like this, especially when it's been explored for so many years."

There are far bigger caves. Mammoth Cave near Cave City, Ky., is the world's longest at 390 miles, with Jewel Cave in Custer County, S.D., second at 157 miles. But Binkley's growth "goes beyond exciting to incredible," said Julian "Jerry" Lewis, a biologist from Borden, Ind., who has worked inside the cave on groundwater and wildlife studies.

"They keep finding more and more and more" territory, Lewis said. "The potential for it to become more immense is growing by the day."