When you think of the many outdoor adventures the Mitten State offers, your mind probably drifts to boating the Great Lakes, hiking to the 300 waterfalls in the Upper Peninsula, walking along rocky beaches, or rafting down the state’s many rivers. Spelunking probably isn’t going to be high on your list, but that’s all about to change.
Once you read about these eight cave sites in Michigan, you’ll want to explore them pronto (maybe not the one with the copious amount of bats, but we’ll leave that up to you).
At 2,034 feet, the Hendrie River Water Cave is the longest cave in the state. It’s found on the eastern side of the Upper Peninsula in the 48-acre Filborn Karst Preserve and is believed to have formed more than 7,000 years ago when the last of the area’s glaciers melted. Now, brave spelunkers from around the state can come tour the cave, which has a small stream running along the floor.
Finding the cavernous passage is no easy feat. It requires passing through a remote highway, a dirt road, an unmarked trail, and a gorge. Fortunately, the Michigan Karst Conservancy arranges guided trips through Hendrie River Water Cave, and they’ll lead you right to it.
Because the cave is completely undeveloped, subject to flooding, and considered advanced, it’s highly recommended that those who are relatively new to spelunking take a guided tour rather than venture out solo.
The Adventure Mine in Greenland Township is among the several man-made caves on this list. From 1850 to 1920, the area was an active copper mine. Now, you can tour the five leftover shafts from May to October.
Tours are operated by Adventure Mining Company, which offers visitors a range of experiences including “rappelling down a mine shaft, underground drilling and blasting workshops, or an easy guided walking tour.”
For an added level of adventure, you can cycle through and around the cave on 4 miles of biking and hiking trails, which take you around some of the old mining buildings. You can even take part in the Miner’s Revenge bike race, which takes place every summer.
Spider Cave, also known as Burnt Bluff Cave and officially identified as 20DE3, is a water-cut cave located on the Garden Peninsula. It’s roughly 20 feet above the base of Burnt Bluff, a limestone cliff that houses multiple caves.
This specific cave was formed 4,000 years ago, but the four pictographs on the walls led to it being listed on the National Register of Historic Places in 1971. It’s believed that humans began living in the cave around 1200 B.C. The most famous and noticeable pictograph is called the “Spider man” as it depicts a man connected to a spider.
To see the ancient illustration for yourself, head to the shore of Big Bay De Noc along Lake Michigan.
If you’re wary of bats, you’ll want to steer clear of this one as it’s now home to one of the largest bat colonies on the entire continent (we’re talking 1 million bats).
The spooky cave is found near Michigan’s border with Wisconsin in Iron Mountain. Like many of the caves on this list, it’s in a now-abandoned mine. If you want the best view of bats coming in and out of the cave in droves, head there before or after their hibernation (April-May or September-October).
For the best sights and sounds, take the Millie Hill Bat Cave Trail up to the viewing area, complete with benches for your viewing pleasure. Unfortunately, only the bats are allowed in and out of the cave itself—but you can tour one of the area’s old mines.
The history of Mackinac Island’s Skull Cave is just as creepy as its name implies. As the story goes, when Fort Michilimackinac was captured during Pontiac’s Rebellion in 1763, an English fur trader named Alexander Henry hid in the small cave. However, he soon realized that the cave was littered with human skeletons.
In Henry’s memoir, he wrote, “…when daylight visited my chamber I discovered, with some feelings of horror, that I was lying on nothing less than a heap of human bones and skulls, which covered the floor!”
There’s a sensible explanation for the horror, though, as it’s believed the area was formerly a burial ground for Native Americans in the 18th century—around the time Henry hid away.
Get directions to the cave, which is inside Mackinac Island State Park, here.
The Eben Ice caves can be found on Grand Island just outside of Marquette in the Upper Peninsula. In the wintertime, melting snow freezes as it runs over the cliffs of the Rock River Canyon Wilderness Area, forming cave-like formations of ice.
If you want to see the caves for yourself, it’s recommended that you get ice cleats to prevent any slipping. You can even climb up the ice if you’re brave enough.
The Alger Underwater Preserve of Lake Superior stretches from just west of Munising all the way to Au Sable Point. Although it’s most famous for the 15 shipwrecks found on the lake’s floor, scuba divers and snorkelers can also explore the area’s shallow sea caves, which are only about 20 feet deep.
Formed by waves hollowing the sandstone cliffs of Pictured Rocks National Lakeshore over time, the caves house large fish and have enough light for underwater photography. Divers of all skill levels will enjoy the underwater adventure.
Considered the only actual cavern in Michigan, Bear Cave was formed more than 10,000 years ago due to glacial drift. Inside the roughly 150-foot cave with 6-by-8-foot passageways, you can find ancient fossils, cave pearls, and glacial boulders.
One of the several “hidden rooms” has a very compelling history. Not only was it used to hide formerly enslaved people as part of the Underground Railroad, it also contains the largest population of Eastern Pipistrelle bats in Lower Michigan. Plus, the whole cave was reportedly used by bandits in the late 19th century, which is how it became one of the filming locations for the 1903 film The Great Train Robbery.