There's something almost universally sacred about ice caves. For millennia, humans and animals have used them for shelter and as sites of ritual. There's no telling what secrets they hold, but adventurous travelers can find out at plenty of locations all over the United States.

By definition, ice caves are caves that contain a significant amount of perennial ice. Most ice caves are in lava tubes, which are round passages that snake inside ancient volcanic mountains. At some point in history, the tubes acted as conduits for flowing lava. They are distinct from glacial caves, which are cavities found within glaciers. In laymen's terms, the label 'ice cave' is used to describe both types of caves.

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Darby Canyon, Wyoming

Wyoming is known for its expansive beauty and natural phenomena, so it shouldn't be all that surprising that the state is home to a massive, maze-like ice cave. Darby Canyon Ice Cave can be found inside the Bighorn Mountain range. Getting to it isn't easy, and requires visitors to hike around six miles through Fossil Mountain.

Keep in mind that exploring the Darby Canyon caves can be tricky and requires ample preparation and equipment. The ice cave itself is vast and confusing, which makes it easy to get lost in. Non-professionals should not wander too deep into the dark, icy caverns.

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Big Ice Cave, Montana

The Pryor Mountains in Bridger, Montana are riddled with caves. The most popular cave is called Big Ice Cave. From the Big Ice Cave Picnic Area, the entrance is a short hike along a wooden plank path.

A little past the entrance, there is a steep drop that creates a sub-chamber in the rock. Due to the unique way in which is the cave is oriented, freezing air that flows in during the winter months is trapped inside, keeping the temperature below freezing all year long and maintaining an icy interior.

Big Four Ice Caves, Washington

It's no surprise that Washington state would have its share of ice caves. A stunning feature of the Cascade Mountain range, Big Four Mountain is over 6,000 ft tall. The top is covered in so much snow that avalanches are known to occur. Over the millennia, the avalanche debris has formed an entire shelf of ice near the bottom of the north face, which, thanks to the continuous shade provided by the mountain, stays frozen throughout the year.

In the summer months, snowmelt streams flow beneath the avalanche debris and freeze again in the winter, forming semi-glacial ice caves.

There is a footpath that leads to the site of the ice caves, and while it is open to the public, officials recommend that hikers stay out of the caves themselves. The caves have been known to collapse and flood, so it's best to look at them from afar.

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Giant Ice, New Mexico

Incredibly, there is an ice cave in the unlikely state of New Mexico. The El Malpais Mountains are full of ancient lava tubes, which foster the ideal conditions for ice caves to form.

The name "El Malpais" translates to "badlands", which is a good indicator that the caves are difficult to get to and traverse. The floor of the cave consists of slippery boulders and unstable ice. Only experienced and equipped rock climbers and spelunkers should attempt to enter the caves, many of which are unexplored.

At certain times of the year, translucent ice columns descend from the ceiling in the center of the cave, which is a magical sight to behold.

Crystal Ice Cave, California

Lava Beds National Monument in Tulelake, California is home to the highest concentration of lava caves in the United States. Many of the lava caves are also ice caves, but the most impressive and famous one is Crystal Ice Cave - aptly named after the ice formations that populate the interior, many of which are transparent and aesthetically pleasing like crystal.

Snowmelt flows into the cave, which forms the solid ice floors. In the winter months, the water that pours into the cave is frozen solid, creating ice columns and waterfalls. The water that drips onto the floor leads to the growth of rounded pillars made of clear ice that emerge from the ground up, similar to how stalagmites are formed out of rock.

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Mendenhall Glacier Ice Caves, Alaska

No description of ice caves in the United States would be complete without mentioning the Mendenhall Caves in Juneau, Alaska. The Mendenhall River drains into Mendenhall Valley in Alaska, where it transforms into the Mendenhall Glacier and Lake.

Unlike other caves in this article, these are glacial caves, as they exist as cavities within a glacier. The luminous blue interior of the caves is probably what most people associate with an ice cave. What's fascinating about the Mendenhall caves is that they are a short trek from Juneau, the capital city of Alaska, and a lot more accessible than most people would assume.

Avoid the hassle of flying to Iceland and experience the magic of these frozen wonders from within the United States. The caves listed in this article are just a few of the many ice caves found in the country. Keep in mind that due to changes in the climate, ice caves and glaciers all over the world are melting, so see them soon before they all become sites of collapse and flooding.

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