Nearly two million years ago, deep under the ground, a hole in the rock began to form. For thousands of years, water has flowed through the rock and carved out our cave, creating a space waiting to be filled.
Today, water continues to drip into the cave, bringing with it dissolved crystals that fuse together to form intricate and varied shapes. Our cave contains the oldest dated cave formations in the Midwest and has some of the best variety in formations seen in the United States.
Something New Above Ground
Across just over 100 acres, the park is covered in woodland, restored prairie and savanna, and a maintained lawn and rock garden–perfect for exploration, picnics, and the occasional stop to smell the flowers.
Our brand new Visitor Center sits comfortably in the landscape, with large windows offering panoramic views to the prairie, woodland, and garden that surround it. The Rock & Fossil Shop, built in 1941, sits on top of the cave entrance and boasts a variety of specimens from around the world–but never from our cave.
Who Are We?
Cave of the Mounds is a show cave in the Midwestern United States. At 1,692 measured feet, it is the fifth longest cave in Wisconsin and contains the oldest dated cave formations in the Midwest. Accidentally discovered in 1939, tours have been given at the cave continuously since 1940 to millions of people from around the world.
We are a National Natural Landmark designated in 1988 as a “site which possesses exceptional value as an illustration of the nation’s natural heritage and contributes to a better understanding of man’s environment.” We are known as the jewel box of America’s caves for our extraordinary cave decoration which includes examples of nearly all known cave formations.
Over several decades, a concentrated effort has been made to restore the native prairies and oak savannas that used to cover this land. A conservation easement of thirty acres was also created in the woodland in partnership with Groundswell Conservancy to protect the park grounds from encroaching urban development.
Cave of the Mounds Timeline
1828
Ebenezer Brigham Founds Blue Mounds
Brigham was a business man and politician born in 1789 Massachusetts. In 1818, he came to Wisconsin to participate in the lead rush and founded his homestead in 1828 as what we now call the town of Blue Mounds.
1883
Historic Barn Built
After Ebenezer’s death, his property went to his nephews as he had no children of his own. J.R. Brigham moved to Blue Mounds and built the barn that you see today, and his family farmed it continuously until the 1980s.
1903
Quarrying Begins
As farming continued, the Brighams discovered high quality limestone beneath their land and began a small quarry South of the barn. It was used sparingly for three decades and was often visited by local geology groups to study fossils of ancient life.
August 4, 1939
Cave of the Mounds Discovered
While blasting for rock in the quarry, workers ripped open two large holes in the ceiling of a then-unknown cave. As they descended into the darkness, they realized that they had something much larger–and much more valuable–than any rock they could harvest. All quarrying stopped, and Cave of the Mounds was born.
May 1940
Open For Business
After putting in wooden walkways and a lighting system, the cave opened for tours on Memorial Day Weekend just 9 months after discovery. Within the first 6 weeks, over 50,000 visitors came to see the cave for the first time.
1941
Rock & Fossil Shop Built
The hub for all cave activity, our gift shop was built on the quarry floor directly on top of the cave entrance to help protect it and make entry easier. It is built with locally sourced limestone and still has the original doors today.
1979
Visitor Center Built
As visitation grew, we knew that we needed more space. The Visitor Center was built to allow guests to have a better experience and even came equipped with an in-house restaurant–the Runestone.
1988
National Natural Landmark Status Achieved
After several years of effort, Cave of the Mounds was officially designated as a National Natural Landmark which allowed us a partnership with the Department of the Interior and the National Park Service.
2001
Biome Restoration Begins
The original ecosystem that covered the cave had long since been neglected, so a great project to restore and conserve the native prairie and oak savanna landscape was undertaken to preserve the natural landscape.
2014
Research Partnership Begins
While our cave has been the subject of research several times over the years, the most recent research began in 2014 when Dr. Cameron Batchelor started taking small samples of our cave formations, providing information on their age, seasonal growth, and ancient precipitation rates in the area.
June 2024
Visitor Center Renovated
Cave of the Mounds once more grew too big for its shell, and in October of 2023 we broke ground to rebuild our Visitor Center. This building was updated with the future in mind and should serve us well for years to come.