Let's Go Spelunking - Right Outside South Bend!

Bear Cave in Buchanan, MI is a destination worth the trip... once it reopens

BY AARON HELMAN // POSTED MARCH 12, 2025

Caves aren't exactly a Midwest specialty - at least not in this part of it. If you head south into Indiana, you'll find sprawling underground labyrinths like Marengo Cave and Bluespring Caverns, but not up here. And for that, you can thank the Ice Age.

When the glaciers bulldozed their way across Indiana, they did a real number on the landscape. Down south, they scraped away the top layers of rock and soil, exposing the limestone deposits underneath, the perfect material for cave-making. But in Northern Indiana and Southern Michigan, the glaciers did the opposite: instead of revealing limestone, they buried it under a thick layer of glacial leftovers: sand, gravel, clay, and whatever else they were carrying at the time. It's like Mother Nature swept everything under the rug and called it a day.

This is bad news for Michiana's cave fans. Caves form best in limestone through a process called karstification, where water slowly dissolves the rock over thousands of years, creating the massive voids that make for great underground adventures. But if the limestone is buried or missing entirely, there's nothing for the water to work with. That's why Northern Indiana and Michigan's Lower Peninsula are practically cave-free zones.

Except for one.

Bear Cave in Buchanan, Michigan is a geological misfit. It's the only cave in the Wolverine State's Lower Peninsula, and there's not another one for hundreds of miles in any direction. And unlike its karstic cousins down south, Bear Cave wasn't patiently sculpted by slow drips of water over millennia. It was ripped into existence by a whole lot of whooshing and tearing.

The cave was violently delivered into existence by the repeated flooding and receding of the St. Joseph River. As the river carved its way through the region, it found a weak spot in the local dolomite, a rock similar to limestone but much harder to dissolve. Instead of wearing it away drop by drop, the river forced its way through, scouring and eroding the rock to create underground passages. Over time, swirling floodwaters and rushing currents hollowed out the cave, shaping it into the small but fascinating geological anomaly it is today.

The cave is at least 25,000 years old, and of course, that's only the beginning of the story.

In the years following the formation of Bear Cave and the settlement of Michigan, Bear Cave developed stalactites and protected ancient fossils and alloys. Later, when the river flooded and carved out even more of the rock than it had originally, it laid bare those fossils, and many of them are still visible. An ancient jawbone is as much a part of the wall of the cave as it is something to view within the cavern.

During the years when the Underground Railroad ran through Michigan, the cave became a cool hideout on warm Michigan nights, and a tour of the cave's abbreviated tunnels reveal alcoves that almost feel like historic little bedrooms. A sign warns tourists not to swim in a deeply formed pool that forms something a lot like a natural bathtub.

Ecologically, Bear Cave has become home to the largest population of Eastern Pipistrelle bats in Lower Michigan, but don't worry, you're not likely to run into any during the daytime.

In the years after the Civil War, Bear Cave became another kind of hiding place altogether when a set of Ohio bank robbers stashed their loot for a time in the faraway cave. The incident is said to have become the inspiration for the classic 1903 short film, The Great Train Robbery, a wildly successful early movie, and one of the longest films at its time - a whole twelve minutes.

Today, Bear Cave is the centerpiece of the Bear Cave Resort - a campground getaway with a pool, boat rentals, group games, and hiking trails. The entrance to the cave is through the resort's gift shop.

Or at least it was until recently.

Traditional karstic caves are not prone to rapid changes, carved as they are by persistent water droplets doing work across centuries and millennia. But Bear Cave is different, a living and growing cave carved continuously by a river that rises and falls. Over the centuries, the flowing river has unearthed new artifacts and built new tunnels. More recently, high water has knocked out one of the cave's walls and has started the process of collapsing the thing altogether.

Beautiful natural places have been threatened by manmade climate disasters for a long time, but this isn't one of those. If Bear Cave is destroyed, it will be at nature's own whims. Caves of this type are transient in all circumstances.

The people at the Bear Cave Resort are doing everything they can to stabilize and reopen Bear Cave but have yet to provide a date for the cave's reopening. When it does, it probably won't be what it used to be.

Of course, a thing isn't beautiful just because it lasts.

We were fortunate enough to visit the cave in June 2024 - just a month before the river washed it out. When - and if - the cave reopens, you should visit it too. If Bear Cave goes away, there's not another one anywhere near us.

I'll warn you: it's not the biggest cave I've ever been in. Actually, it's the smallest.

But it's also the nearest: a historic curiosity, an ecological marvel, and a geological miracle right in our own backyard for as long as it will endure.