Iowa is full of fascinating geographic wonders – like the breathtaking Loess Hills and regions full of Karst Topography. One particular spot gets people talking though – because you’ll need to bring a coat, even if you’re hiking on a 100 degree day! Of course, I’m talking about the Decorah Ice Cave.

The Decorah Ice Cave is located at Ice Cave Rd, Decorah, IA 52101

Google Local / Tony Hess It’s part of a large park system that makes the city of Decorah the perfect destination for a day trip.

You’ll have to do some hiking to get there, so be sure you wear sturdy sneakers and bring everything you need for a short hike.

Google Local / Quang Lam

As you climb higher, you’ll notice signs on the trail pointing towards the Ice Cave.

Google Local / Alex Rau

Finally, there’s a stone staircase that will lead you to this geologic wonder.

Google Local / Isaiah54117

The Decorach Ice Cave is part of the Driftless region of Iowa, where interesting geography, topography, and geology is common!

Google Local / Alex Rau The science behind the cave is simple, but incredibly interesting. This whole area actually was not glaciated during the last Ice Age, so the ice isn’t caused by any sort of glacier that hasn’t yet melted. The cave creates a cold air trap thanks to the way the cave is formed. While I’m sure a geologist could explain it more scientifically, the cave is based around the fact that warm air rises. The entrance is higher than where the ice lies, so the cold cave air remains in the cave all summer long, because the warm air is lighter and escapes from the top. In the winter, sometimes cooler air can get in, though, pushing out any warm air and adding to the chilly temperatures of the cave.

The cave rarely rises above 35 degrees in temperature, and there’s ice on the ground and in the cracks of the rock for most of the year!

Flickr / Michael Massa Ice starts to form on the walls in January, and by May, it’s several inches thick! This ice remains until late August, when it finally melts.

Be sure to bring a flashlight and be prepared for how chilly it is in the Decorah Ice Cave!

Flickr / Michael Massa

Have you visited the Decorah Ice Cave? While you’re there, stop by the charming town itself – after all, it is the Most Beautiful Town In Iowa.

Google Local / Tony Hess

It’s part of a large park system that makes the city of Decorah the perfect destination for a day trip.

Google Local / Quang Lam

Google Local / Alex Rau

Google Local / Isaiah54117

The science behind the cave is simple, but incredibly interesting. This whole area actually was not glaciated during the last Ice Age, so the ice isn’t caused by any sort of glacier that hasn’t yet melted. The cave creates a cold air trap thanks to the way the cave is formed. While I’m sure a geologist could explain it more scientifically, the cave is based around the fact that warm air rises. The entrance is higher than where the ice lies, so the cold cave air remains in the cave all summer long, because the warm air is lighter and escapes from the top. In the winter, sometimes cooler air can get in, though, pushing out any warm air and adding to the chilly temperatures of the cave.

Flickr / Michael Massa

Ice starts to form on the walls in January, and by May, it’s several inches thick! This ice remains until late August, when it finally melts.

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