Current COVID-19 protocol.
Cave of the Mounds National Natural Landmark is located in beautiful Dane County, Wisconsin.  Dane county currently has the following COVID-19 mandate in place [Dane County Mandate link].
 
Cave of the Mounds is dedicated to offering wonderful outdoor recreation, and has protocol in place to help protect our staff and guests. [Our Covid Policy].

 

To help protect our staff and guests, and to support our state and county department of public health departments, please be aware of the following when visiting COTM:
 
  • Dress for the current outdoor weather conditions as well as the 50° Cave and plan to enjoy our beautiful nature trails and outdoor activities while onsite. 
  • A limited number of Cave tickets per hour are issued in order to help maintain social distancing. You may have a wait time outdoors prior to your cave entry.
  • Cave entries are limited to one household at a time in accordance with Dane Counties mandate to allow for proper social distancing
  • Due to COVID-19, our building capacities are monitored and enforced for the safety of our staff and guests
  • If there is a wait time for your cave experience and you do not wish to be outside, you may prefer to wait in your car.  Our parking lot is close by and all parking is free. 
  • Masks are required inside the buildings and inside the cave at all times with NO exceptions.  If you are unable to wear a mask due to health condition, we have these alternative options for you. [Our Covid Policy Link Here]
 
Please do not travel if you are sick, and please adhere to the advice that the CDC has issued including, but not limited to, frequently washing your hands, wearing a mask, and maintaining at least a 6 foot social distance from anyone not in your household.  We understand if the best choice for your family is to visit in the future instead, once the threat of the pandemic has lessened. With your assistance, Cave of the Mounds will be here for generations to come.  Open daily from 9 AM to 5 PM year-round. [Closed thanksgiving, Christmas Eve, & Christmas Day.]
 
 We wish you happiness and great health through the holiday season!
 

Cave FAQs

What is a Self-Paced Tour?

Take a self-paced stroll through this geologic wonder. Entries enter  regularly every day of the year. Your walk will guide you past a stunning array of colorful crystal formations on paved lighted walkways. As you explore, NEW signage will explain the science and history and our staff are stationed in the cave to make sure that you enjoy your experience.

INSIDE THE CAVE

The total surveyed length of the Cave (lengths of the caverns, Meanders, and every nook and cranny added together) is 1692 feet. The straight-shot length of the caverns, from the “South End Collapse” to the end of the “Dream River Room” (as the bat flies, though Cave of the Mounds doesn’t have bats!) is approximately 750 feet. We walk about 1/5 of a mile (about 1100 feet) on the tour.

Distances from floor of Cave to surface:

  • South End Collapse 42 feet
  • Onyx Ridge 48 feet
  • North Cave 57 feet
  • North End Collapse 43 feet
  • Bypass Tunnel 40 feet

Limestone is a porous rock, so air and water pass through it fairly easily. As the barometric pressure changes outside, air passes through the limestone to compensate for the change, thus either drawing air into the Cave or pushing it out.

Bats, coyotes, raccoons, and other trogloxenes that might have used the Cave for shelter would have needed a natural opening to enter and exit through. Before Cave of the Mounds was discovered in 1939, it was a closed system. That means, there were no natural openings from the Cave to the surface above, keeping it hidden for millions of years. Most caves are discovered via a natural opening created by a sinkhole or other natural occurrence, so this unique feature distinguishes Cave of the Mounds from other show caves in Wisconsin.

It takes approximately 100 years for cave onyx to grow 1 centimetre if perfect conditions were to exist. In reality cave formations can take even longer to form.

Your hair grows faster in 6 hours than our cave Speleothems or formations do all year

HISTORY OF THE CAVE

Yes, and it has been since the day it was discovered. The Cave is on Brigham Farm, which was founded in 1828 by Ebenezer Brigham, the first european settler in Dane County. When he passed on, he left the property to his great nephew Charles Brigham, Sr. Charles and his family operated the property primarily as a dairy farm, but occasionally leased quarry rights to local contractors, and thus in 1939 the Cave was discovered! In 1988, Cave of the Mounds earned the National Natural Landmark designation, entering into a public-private partnership with the National Park Service. This partnership ensures that the Cave will be managed & protected for future generations as a prime example of Wisconsin’s Natural Heritage.

Cave of the Mounds was accidentally discovered on August 4, 1939. Workers, who were removing high quality limestone from a quarry on the Brigham Farm, blasted into the Cave. The blast tore the face off the quarry and revealed a great underground cavern. All quarrying stopped and never resumed. The dynamite blast revealed a limestone cave more than twenty feet high opening into other rooms and galleries, all containing numerous mineral formations.

The excitement of the discovery brought so many curiosity seekers that the Cave had to be closed in order to preserve it. Soon, lights and wooden walkways were installed. And, in May 1940, Cave of the Mounds was opened to visitors. Millions of visitors later, the Cave’s wooden walkways were replaced with concrete; a large stone building replaced the original entry building; and theatrical lighting has been installed to dramatize the colors and shapes within the Cave. Picnic areas, walking trails, rock gardens, gift shops and a visitor center have all since been developed.

SCIENCE OF THE CAVE

The mineral calcite is white. Reddish brown colors come from rust deposited by Leptothrixbacteria. Shades of black, purple, and gray come from manganese compounds deposited by Gallionella bacteria.

The water table is roughly 400 feet below the surface. The water table is very slowly lowering as area rivers erode the surface. The local water table is controlled primarily by the Wisconsin River.

Three methods for finding caves are seismic soundings, resistivity testing, and gravity measurements. However, due to the sensitivity of the equipment, such testing can be extremely expensive. Also, it is very difficult to determine the size of underground cavities using surface testing. Gravity testing has been done around Cave of the Mounds; and more recently seismic soundings were tried above the Song of Norway grounds.

For your safety and to protect our fragile cave: Take Photos but no tripods, mono-pods, or selfie sticks. Do not touch the cave. Please leave backpacks in vehicle because nothing is allowed on your back inside the cave. No strollers or framed carriers. The cave is cool. Dress appropriately as the cave is 50 degrees Fahrenheit or 10 degrees Celsius in the cave. No smoking or vaping in the cave. No food, drink, or gum allowed. Only bottled water in the cave.