Iowa’s cave networks are well known, including the world-famous Maquoketa Caves – an inviting, well-traveled cave system that sees countless visitors each year. The Hawkeye State has a few other cave systems, many of which are popular tourist spots. But did you know none of these are the largest cave in Iowa? That goes to Coldwater Cave, located in Decorah’s Cold Water Spring Nature Preserve. You’ve never heard of it? There’s a reason for that – this secret cave in Iowa is not open to the public, and it hasn’t even been fully explored yet! Discovered in 1968 by two University of Iowa students, this mysterious cave is located on private property and is still being explored by experienced speleologists – some of which provided us with detailed video footage that gave us our best look yet at this natural wonder!

However, that doesn’t mean you can’t experience what it’s like inside this ancient cave full of secrets. The best look we’ve gotten of the cave yet comes from an extended expedition that was broadcast on Iowa PBS. It revealed a hidden world of deep caverns and stunning rock formations that were formed over millions of years.

Have you heard about Coldwater Cave in Decorah? You probably haven’t been inside this secret cave in Iowa – unless you’re one of the Hawkeye State’s top speleologists – but let us know about your own cave adventures in the comments section! Iowa DNR detailed the progress in mapping Coldwater Cave on its website if you want to read more.

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