Eventually, the cave was leased to two local businessmen, Mr. Carl P. Brechler and Mr. Fred H. Hanneman. Soon, they developed a plan for making the cave accessible so both young and old could experience this natural, scenic wonder. Brechler and Hanneman worked tirelessly to make the cave available to be opened for guests on May 30th, 1940, just in time for Memorial Day weekend. More than 58,000 visitors would come to see this beautiful cave over the next 27 weeks.
Today, many families, children, and youth groups visit the cave to learn about Wisconsin geology, limestone cave formation, this unique discovery, and to enjoy the interpretive trails and gardens. In 1988, Cave of the Mounds was designated a National Natural Landmark by the Department of the Interior and the National Park Service for its illustrative character, rarity and its value to science and education. While Cave of the Mounds is not a national park, the park service works cooperatively with landowners, managers and partners to promote conservation and appreciation of our nation’s natural heritage.