Chances are you've probably explored some of Iowa's well-known caves. The Maquoketa Caves State Park is a great place to hike and see amazing cave formations. Wapsipinicon State Park in Anamosa has several caves that you can visit. But very few people have ever visited the largest cave in Iowa. It is just too dangerous to visit.

The largest cave in Iowa is called Coldwater Cave and it can be found in Decorah's Cold Water Spring Natural Preserve, according to Only In Your State. You've never heard of it? Don't feel bad. Not many people have, and for good reason. This cave system isn't open to the public and it hasn't even been fully explored!

YouTube via Iowa PBS
YouTube via Iowa PBS
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Coldwater Cave was discovered in 1968 by two University of Iowa students, according to Only In Your State. But getting to this natural wonder is no easy task. The entrance sits on private property and isn't open to the public. The cave is deep, and many places are covered in water, making exploring treacherous. Over the years, nearly 20 miles of caves have been mapped at Coldwater. And for the experts that can reach the depths of Coldwater Cave, the sights are amazing!

YouTube via Iowa PBS
YouTube via Iowa PBS
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Imagine needing scuba gear to reach the largest cave in Iowa. I can't imagine the early explorers braving the dark and cold to discover the amazing sites in Coldwater Cave.

YouTube via Iowa PBS
YouTube via Iowa PBS
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While you and I will probably never know what Coldwater Cave looks like in person, several years ago professional cavers took down members of Iowa PBS. It is the closest that most of us will get to this amazing and dangerous expedition. Who knows what other secrets Coldwater Cave holds?

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