The bidding starts at $899,900, cut from Rush's original asking price of $1.2 million.
Rush bought the property near Harrison in 1988 and began giving tours in 1992 to the two accessible caves, Mystic cavern and the Crystal Dome cavern. A third cave on his 28-acre property, Not Much Sink cavern, remains too dangerous for tours.
But business has dropped since a nearby amusement park closed in the 1990s. Rush said the Mystic Caverns still get about 15,000 visitors each year.
Rush said he wants to sell the caves to become involved in Christian ministries. He also joked that he tiring of being a tour guide.
"It's always been a struggle for me, because you have to entertain people. ... I'm really tired of trying to entertain people," he said.
Rush acknowledged the tight real estate market but said he hoped to sell the caves to a cave-diving enthusiast with a little spending money.
"It's a tough time in the marketplace to get a buyer I think for any real estate, and I don't think this business makes enough money" to make mortgage payments, Rush said. "However, if you had some money and you were not afraid of risk ..."
Vickie Martin, a real estate agent for the caves, agreed. "It's a tough sale. You've got to find the right person," she said. "It takes a lot of time and energy and run it. It's not something you can buy and let it run itself. You've got to take an active interest in it."
Rush said he had been quietly shopping the caves around for two years but took the sale public when no takers came forward.
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