The old mining caves on East Osage Street, now owned by Phil Zahn and Joe Bosse, will be the backdrop for the second annual Cave Jam Sept. 14-15.

The caves have been cleaned and lighted and will be open to the public during the event.

“They can explore the whole thing,” Zahn said.

Friday Cave Jam hours are 5 p.m. to 1 a.m. and Saturday hours are 10 a.m. to 1 a.m.

The cost is $5 on Friday and $10 Saturday. There will be no charge for children accompanied by adults.

Activities will include carnival rides, vendors and fire dancers.

Billed as a rock concert in front of the caves, the event is expected to draw a large crowd.

Two bands will perform that Friday evening — Jeremiah Johnson and Tony Campanella.

On Saturday, Geo’s Trio, Blended 328 and Toby Tomlinson and Trigger Proof will perform.

On both days, music will play onstage until midnight. For the next hour, until 1 a.m., a disc jockey will play music.

To date, 30 vendors have signed up to offer food, face painting and shaved ice. There will be two beer gardens.

Anheuser-Busch’s Gray Eagle distributing will bring an interactive mobile to entertain youngsters. There also will be washers and volleyball in the cave for anyone who wants to play.

On Thursday, Sept. 13, Klance Stages of Pacific will set up the big stage. Logic Systems will provide the sound system. Top Shelf, St. Louis, is promoting the event.

Zahn, who is the orchestrator, says he has more or less a hold on every element of the event.

“I’ll be happy when it’s over and I see it has lived up to its billing,” Zahn said.