BONNE TERRE — In 1864, the St. Joseph Lead Co. opened Bonne Terre Mine to gather the rich supply of lead in the earth. Now, almost 150 years later, that space serves as the Billion Gallon Lake Resort.

“Bonne Terre folk really don’t know what’s going on here,” said Steve Branom, dive control specialist and tour leader for the dive resort. “It’s weird!”

The mine opened for tours in 1968 after area businessmen bought the 946-acre property.

“I’ve been working there 10 years, and I still love what I do,” said Donna Jones, general manager of the mine. “I love to see the people’s faces when they are totally in awe of what is there and what isn’t there as well.”

The lead was mined using the pillar system. This means that the workers would get all of the rock out of a certain area and leave nothing but column-like pillars behind. The walking tour of the resort takes visitors through and around the pillars. The tour is not just an eye-catching experience — It’s a history lesson.

“The little kids are having so much fun that they don’t realize how much history they are getting at the same time,” Jones said.

If visitors choose to take the boat tour along with the walking tour, they experience another part of the mine in a pontoon boat that goes deep into the lake area.

“You get a better perspective,” Jones said of the tour. “It just makes the experience that much better.”

On the boat tour, visitors also get a first-hand experience with the scuba divers. The boat never goes over the divers, but by looking left and right over the boat, tourists can see the divers exploring because they carry glow sticks that illuminate the water.

The dive resort was created in 1979 by Doug and Catherine Goergens of West End Diving in Bridgeton. They opened it to divers in 1981.

“It was my wife’s idea, and she’s still the driving force behind the entire operation,” Doug Goergens said. “She said that we needed a place to dive so that our business could grow. We have relatives in Bonne Terre, so we drove down to check it out.”

After purchasing the mine and surrounding property, the work that went into preparing the empty space for divers took two years and was extensive: more electricity needed to be wired throughout, lights had to be put in place, the dock had to be built, and the dive courses had to be mapped out.

“Now, it’s incredible,” Goergens said. “People from Florida are coming to dive in Bonne Terre, Missouri. They have coral reefs to dive, but they are coming here.”

“It’s like being in outer space,” Goergens said. “It’s about as close to Superman as you can get when you leap from peak to peak under there. The mystique and splendor of it all can only be appreciated by the diver.”

West End Diving does not just use the Billion Gallon Lake Resort for tours.

“It’s the perfect place to train our students,” Goergens said.

West End Diving certifies divers and trains staff for the company in the mines. It takes two separate weekends to get an open-water certification. The first weekend there are classes in St. Louis at West End Diving. Weekend No. 2 includes dives in the mine.

“Safety here is incredible,” Branom said. “It makes it more fun for divers. It’s like a jungle gym down there.”

There are 24 trails within the lake, each increasing in difficulty.

“You have to practice buoyancy — your ability to stay level — and that’s difficult to do,” Branom said. “New divers usually have trouble with it.”

A dive includes 10 to 12 divers on a trail and lasts about 45 minutes.

Although scuba diving in the mine is not something that can be accomplished in one weekend of a family vacation, the tour alone is spectacular for all members of the family.

For more information on the Billion Gallon Lake, including times and prices of walking and boat tours, go to 2dive.com, or call Doug Georgens at (314) 209-7200.