This story originally appeared on Travel + Leisure.
When you hear the shiver-inducing term “ice castle,” you may imagine a childhood creation that is more mound than art.
But the Ice Castles Project is far from any igloo-shaped playhouses of years past.
Throughout the North and Midwest—specifically Utah, Minnesota, Wisconsin, Alberta, and Lincoln—you'll find grand designs you can walk through that are made using the “dribble” method.
Every year, the founders of the Ice Castle Project head to some of the coldest places in North America to set up drip pipes, a tool used to kick off these massive structures. Icicles form off of the pipes, creating long “dribbles” that serve as the base of the castles.
Once there's enough of a base, Ice Castle sculptors get to work forming the chilly caverns. These castles open up to visitors by early January, but the bases are set weeks in advance.
The later in the winter season you set off to see these castles for yourself, the bigger they'll be. Atlas Obscura notes that the sculptures grow by thousands of new icicles per day.
From the outside, the castles give off a cavern vibe—the dribbles look a lot like stalagmites. But once inside, visitors are treated to a winter wonderland of light. Much like the glacial cave tours people travel miles to experience in Iceland, every day brings a slightly different view to visitors.
The Ice Castle Project website has tickets available for the castles in Midway, Utah; Lincoln, New Hampshire; Stillwater, Minnesota; Wisconsin Dells, Wisconsin; and Edmonton, Alberta.
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