LOUISVILLE, Ky. (WDRB) -- One-hundred feet underground, finishing touches are being put on what Mega Caverns officials call the largest indoor bike park in the country.

After four months of construction, Louisville Mega Cavern's 350,000 square foot bike park will open to the public Monday. 

Alec Zaremba with Louisville Mega Caverns said from the day they decided to build the park, it just kept growing.

"We were going to look at a warehouse that was about 20,000 square feet, and then it turned into 350,000 square feet very quickly."

With over 45 trails, jumps and features, builders say they used around 10,000 tons of dirt.

"We started bringing in the dirt, and we didn't have enough room," said former pro bmx rider and lead designer of the project Joe Prisel. "As a typical builder, I wanted more room -- even though its the most I've ever had, I still wanted more."

The Louisville park isn't Prisel's first endeavor. He started building jumps when he was 12-years-old. Now he gets paid to build parks around the world. He said Mega Cavern is the largest indoor park he's ever designed.

Zaremba said the cavern's customer base generally consists of tourists, but they believe the bike park will attract local bike enthusiasts.

"We think with this, we're going to bring in a lot more local people and a lot more of an enthusiast market. Much less of people traveling through."

Tickets are already on sale for Monday's soft opening. The price for a full day is $40. A half day is $24. Season tickets are not yet available.

Bike rentals should be available at the cavern starting in April.

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