Organizers said lower entry fees and early fall weather combined to show that Cave Jam, the East Osage outdoor music festival in front of the caves, has staying power.

Exact numbers were not available for the second annual Cave Jam, held Sept. 14-15, but it was clear that several thousand patrons, many of them families with children, poured into the fenced area over the two-day festival.

“Maybe it’s partly because it’s the first light-jacket weather,” said a gate security worker dressed in a bright red Cave Jam T-shirt.

Crowds gathered during the daylight hours to watch bicycle circus riders pop wheelies on a steep incline that sent them careening into the air and fire dancers who performed in the street. At the east perimeter, a small corral was set up for youngsters to take pony rides or hand feed the small sheep and pigmy goats.

The large artificial cave openings served as the entry to the Cave Jam grounds, requiring patrons to walk beneath the high ceiling chamber of two of the caves. Patrons were free to walk among a string of brightly painted muscle cars and an antique metallic green pickup truck.

Security crew members, with hand-held walkie-talkies, stayed connected to Ryan Richardson, Third Rail general manager, who offered directions to patrons.

As the sun began to set, crowds set up their lawn chairs in front of the huge stage provided by Pacific-based Klance Staging Inc. to watch a series of well-known bands that pulled their big black tour buses up behind the stage.

A sound booth set up in front of the stage operated the Logic Systems sound system, for music that was directed toward the east and was barely audible two blocks west.

Several thousand patrons relaxed in lawn chairs to watch a series of bands belt out rock ‘n’ roll or country music. Six carnival rides helped to attract families with children.

“People are becoming more familiar with the caves,” said Phil Zahn owner/operator of The Third Rail and owner of the caves, who sponsors the event.

“We’re having sand volleyball games in the caves every other week,” he said.

The net games draw both men and women adult players and people who just like to hang out in the cave and watch.

Zahn won’t say exactly how much he has spent to clean out the floors of the old mining caves, once used to hide demolition materials from the old Hardstone Brick Company, and install lights high along the cathedral like columns, but Cave Jam is just one way to recoup the investment.

“The caves are here to stay,” he laughs. “It makes sense to find ways to use them commercially.”

In the coming weeks, workers will begin to decorate the caves and install colored lights for a Haunted Halloween event inside the caves.