Joy Marquardt

For USA TODAY NETWORK-Wisconsin

Looking beneath the Earth’s surface, caves bring to light a whole new world of exploration.

With more than 400 public and private caves documented in the state, the Wisconsin Speleological Society is working to restore caves that were formed more than one million years ago.

“It’s the last frontier as far as discovery in the world,” said Kasey Fiske of Prairie du Sac, chairman of the Wisconsin Speleological Society. “You never know what you are going to find.”

Four of the largest caves and cave sites in Wisconsin, Cave of the Mounds, Crystal Cave, Ledge View Nature Center and Cherney Maribel Caves County Park, are open for public tours.

Cherney Maribel Caves County Park

Located halfway between Green Bay and Manitowoc near Cooperstown, the Cherney Maribel Caves are part of the Manitowoc County Parks Department.

The six main caves in the park were discovered as early as the mid-1800s to as recent as 1984, when New Hope Cave the largest cave in the series was found.

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“New Hope Cave is becoming quite an attraction,” said tour guide Mike Sobush of Francis Creek, a member of the Wisconsin Speleological Society. “It’s not the largest or longest cave in Wisconsin, but it’s probably the prettiest cave as far as formations go.”

Guided tours of New Hope Cave and several of the larger caves in the park are given the third Sunday of each month May through September and the first Sunday in October from 10 a.m. to 3 p.m.

Sobush estimates an average of 300 to 400 people per day take the guided tours during the summer months. The 20- to 30-minute tours are free with donations accepted.

“It’s becoming very popular,” he said. “We broke a record last month with 456 people coming through on a Sunday afternoon.”

Spelunking or self-guided tours are available in some of the smaller caves in the park from 6 a.m. to 8 p.m. seven days a week.

Cherney Maribel Caves County Park, the oldest park in Manitowoc County, has 75 acres of hiking and biking trails and picnic areas in addition to the caves.

“I think the park is a hidden gem,” said Gary Robinson, superintendent for the Manitowoc County Park Department. “The caves are very secluded, it’s a beautiful park. I think even the locals don’t realize what they have in their own backyard.”

Ledge View Nature Center

The Ledge View Nature Center two miles south of Chilton has four main caves to explore with scheduled guided tours. The largest of the caves has a cavern with 40-foot ceilings and both a regular walking tour and adventure tour with added passage ways and tunnels are available.

Cost for the walking tour is $6 per person and $7 per person for the adventure tour. Children must be five years old and up to participate. The adventure tour consists of crawling through tunnels, climbing ladders and viewing an additional cave. Participants must bring their own flashlights.

“Generally, people know we are a nature center and not a commercial cave,” said Louise Marum, assistant naturalist for the park. “The biggest thing with our caves you can crawl in tunnels and get dirty and physically experience the caves.”

The park schedules school tours for more than 12,000 students each spring and fall. Public tours are held on the weekends and weekdays by appointment.

As part of the Calumet County Park Department the park has 105 acres of hiking trails, a 60 foot observation tower, a nature center with a 600 gallon Sturgeon exhibit, ice fishing exhibit, and a bat barn which are free of charge and used for educational programs at the park.

A Halloween party will be held in the caves Oct. 21 and 22, with candles and jack-o-lanterns lighting the rooms and passageways and educational skits presented by area high school students.

Crystal Cave

Discovered in 1881 by two local farmers, Crystal Cave near Spring Valley, an hour west of Eau Claire, was opened to the public in 1942.

“It’s such a unique environment, it’s not something you get to see every day,” said owner Eric McMaster, who is in his fourth season of operating the cave along with wife, Kristen.

The largest commercial show cave in Wisconsin, the facility has spacious rooms and passageways similar to the hallway in a home. The paved walkways more than 70 feet below ground are well lit and the temperature remains an average of 50 degrees year round.

Group tours with up to 20 people are available seven days a week April 1 through October 31. School and special group tours are arranged by appointment.

McMaster recently added a Wild Cave Tour of the rustic South Portal Cave. The three-hour advanced tour limited to six individuals includes a one-hour seminar about the basics of caving.

Cost of the regular walking tour is $14.98 for adults, $9.98 for children and under age three free. Wild Cave Tours are $29.98 including equipment and educational seminar.

Cave of the Mounds

Special events and one hour walking tours treat visitors from all over the world at the Cave of the Mounds near Blue Mounds, 30 minutes from Madison.

Open year around seven days a week through November the show cave runs tours every hour during the weekdays and every half hour on the weekends.

“Ours is a show cave,” said operations manager Kim Anderson. “Our tours are a leisurely walk through the caves with information given on the tours.”

Discovered by a routine quarry blast in 1939, the caves receive more than 100,000 visitors a year. Guided tours of the caves are $17.95 for adults, $9.95 for children age four to 12 and under four free.

A Cave After Dark series provides monthly activities and entertainment in the caves specifically for adults. An Oktoberfest scheduled for Oct. 22 will host beer tasting in the caves.

Fall family events include “HOLLOW-een in the Caves”, Oct. 28 to 30 featuring a costume party with trick-or-treating for rocks and fossils. Cave of the Mounds welcomes visitors for the holiday season with caroling in the caves in November and “Jingle Rock” in December with holiday music and bell ringing in the caves.

FOR MORE INFORMATION

Cherney Maribel Caves County Park, 15401 Co. Road R, Cooperstown. Phone 920-683-4189 or visit www.maribelcaves.com.

Ledge View Nature Center, W2348 Short Road, Chilton. Phone 920-849-7094 or visit www.ledgeviewnaturecenter.com.

Crystal Cave, W965 State Road 29, Spring Valley. Phone 715-778-4414 or visit www.acoolcave.org.

Cave of the Mounds, 2975 Cave of the Mounds Road, Blue Mounds. Phone 608-437-3038 or visit www.caveofthemounds.com.