Jack Murphy

Best caves in the state and how they were formed

While acres of farmland may dominate America’s Dairyland, more than 400 caves are tucked away across the state. From a land bridge that burrows through the rolling hills of Manitowoc County to some only accessible by water, Wisconsin hosts a surprising variety of caves. It makes sense, too. Across the state, aquifers supply towns with water through a network of caves. Check out these subterranean hollows to take your next adventure underground! 

Photo courtesy of Peter Gorman, Creative Commons Licensing

Cave of the Mounds stalactites

Fittingly named after Blue Mounds, where it’s located 30 miles west of Madison, this destination is more than just its namesake. Featuring a sinkhole and winding trails through Chert Creek, Cave of the Mounds offers activities both above and below ground. The cave formed in the Ordovician Period when shallow seas covered what is now Wisconsin. They froze into a 20-million-year ice age that wiped out almost half of all marine species. The mollusks of this period deposited abundant minerals, bolstering the state’s status as an agricultural powerhouse.

Photo courtesy of Wisconsin Great River Road

Crystal Cave

Eight miles from the southwestern border of Wisconsin, Pierce County is home to Crystal Cave, a three-level cave network marked by a variety of natural limestone formations. These formations naturally stack to create walls resembling a layer cake. During the winter, it hosts four different species of bats native to Wisconsin and Minnesota. These bats can eat up to 300 insects each evening!

Photo courtesy of Eagle Cave Resort

Eagle Cave

Found 60 miles from Devil’s Lake, Eagle Cave is the largest onyx cave in Wisconsin and the first in the state to be commercially owned. While the gemstone is known for its distinctive black and white bands, onyx can actually span the entire color spectrum. Caves are rich with the mineral calcite and form when an abundance of it is dissolved in groundwater. Geological forces can crack the exterior limestone of a cave and over time, water will flow in with additional minerals to form the gemstone.

Photo courtesy of Chumlee10, Creative Commons Licensing

Devil’s Island Sea Caves, Apostle Island National Lakeshore

Exposed to the ferocity of Lake Superior, in the upper reaches of the state, these red-banded caves along the northern coast of Devil’s Island feature a ribbon-shaped tunneling network accessible by kayak. At night, howling winds surge through its tunnels at night, producing the fearful bellow of its namesake. When you get close enough, you’ll notice the layers of sand pressed over thousands of years by shallow ponds.

Photo courtesy of Joshua Mayer, Creative Commons Licensing

Cherney Maribel Caves County Park

Rivaling only Cave of the Mounds, Cherney Maribel Caves are a perfect weekend trip for families of all ages. With extensive trails and smaller caves perfect for youngsters to safely explore, this Manitowoc County park, 90 miles north of Milwaukee, allows visitors to take a leisurely approach to cave hunting. Formed by glacier movements, these gentle plains are a part of the Niagara Escarpment. Known primarily for the falls that bear its name, this ridge stretches from Illinois, Wisconsin, Michigan, Ontario and all the way to New York.

DARK page photo credit: Illustration by Jack Murphy