Discover the 5 Deepest Caves in the United States

Humanity has always strived to reach beyond, to touch every mountain peak. From the tips of mountains down to the ocean floor. It is no wonder that we would also seek to explore what lay below our feet within the deepest caves.

Cave exploration, or spelunking, is more typical of a pastime than one would think in the United States. It’s frightening to consider the world’s weight literally on your shoulders as you climb deeper into a pit that likely has only one exit.

Wildly, some of the deepest caves in the U.S. are hard to find information on. Spelunking isn’t the same as mountain climbing, and it seems, fewer people do it because the difficulty levels are higher.

There is also just a point at the depth of every cave where there is no further to explore, at least for the moment. A saying typical for cave divers is, “I don’t do this because it’s there. I do this because of what’s not there yet.” Cave depth is constantly fluctuating as caves themselves are discovered.

Cave systems are fluid in depth because cave divers are always looking to find that little extra length or depth. They yearn to discover.

Cave divers are also secret keepers. They don’t like to reveal exact locations to people and network amongst themselves. It makes cave diving seem even more niche and risky.

What Does Depth Mean?

We need to get this out of the way. The difference between length and depth is quite essential. The depth of something is how deep it goes, right down to its lowest point, and the length is how far it measures. 

A cave could be two miles deep and thirty miles in length, and the depth is straight down. If you were to take a ruler, you could measure to the depth, while you would need a measuring tape for length.

The Five Deepest Caves in the U.S.

Clarifying the top five deepest caves in the United States can be tricky, especially when it comes to depth and length. Depth isn’t always clear-cut as caverns can change, and some are not very accessible, so not much information is available.

Our list, as of March 2022, is this:

1. Tears of the Turtle Cave
2. Lechuguilla Cave
3. Virgil the Turtles Great House Cave
4. Columbine Crawl
5. Great EXpectations

Most of the information on cave length is thanks to Caver Bob, aka Bob Gulden, for providing a list of the depths of caves in the United States. Some information may have been updated but so far isn’t available online.

That is just the way cavers try to keep the worlds they travel secure and safe from the average interloper like us.

1. Tears of the Turtle Cave in Montana

Found within the Bob Marshall Wilderness area, the Tears of the Turtle cave is located within the state of Montana and is a whopping 1863 feet deep. A hike of 22 miles is necessary before you can even get to this cave system.

Spelunkers who choose to travel to get to this long path into the earth are braver than many. The climb becomes more difficult as you go onward and has many dead ends or short-walled passages to explore. The longer you spend, eventually the deeper you go.

It is found on the face of the cliffs of Turtlehead Mountain, which explains its name a bit. The caverns find their end at a large passageway canyon. The ground is often a dangerous mixture of mud and sand that is difficult to cross. 

There is still a chance that eventually, people or equipment could go deeper into Tears of the Turtle Cave, so we must wait and see what the future holds.

2. Lechuguilla Cave in Carlsbad

Lechuguilla Cave used to like to trade around the title of the deepest cave in the United States, but now it defiantly sits here in second place at 1604 feet. It is named after a spiny plant that often nicks hikers unawares, and this is because of a surprise to be found in this cave.

The surprise is a deep pit called Boulder Falls with a depth of 150 feet and tends to let rocks come loose and fall while people try to climb along it. The cave has been known since 1914 but wasn’t fully accessed until 1986.

To explore Lechuguilla Cave, one must wear a wetsuit tough enough to withstand sharp rocks and be ready to contort through it. The opening to this deadly cave is locked, and the public is not allowed access to it, only experts. This is for safety reasons.

3. Virgil the Turtle’s Great House Cave 

This is the second deepest limestone cave in the U.S. and was mapped and measured in 2006 to be 1586 feet deep. Much of this cave is wide and easy to explore, so it’s a wonder there isn’t more information out there on it.

It is presumed Virgil the Turtle’s Great House Cave was unearthed when glaciers melted. It resides on a cliff face and has muddy, hard-to-traverse terrain leading up to it. Much of the bottom of the cave is often soaked in mud, so maybe that deters visitors in Montana.

4. Columbine Crawl

Once considered the deepest cave in the United States, Columbine Crawl is now in fourth place. There is not much information on Columbine Crawl, and we know that it is in the Teton Mountain Range and is not easily found or accessible. Most of the year, its entrance is hidden beneath the snow, so you must know when to look for it and where.

Cave diver Mike Beer was the first to spelunk down this cave in 1980. The cave is one of the deepest limestone caves in North America at 1551 feet. It begins with a long crawl and then drops twice through the stone. It is a complicated and hard-going climb, not for the fainthearted.

Spelunkers must travel through water, rotten stone, and sewer pipes that cross through the shale. The cave does branch out through areas with waterfalls and wild winds. There is an excellent reason for the lack of insight into this cave.

5. Great EX(pectations) Cave 

Often known as Great X, it is the third deepest limestone cave in the United States and there is a lot of water to wade through when it comes down to it. Great X is 1408 feet deep and located in the state of Wyoming, as are a few on this list.

When spelunking here, one can take two different kinds of trips, and neither is for inexperienced people. Both trips involve crossing waterways, one where you even have to swim through the water depending on the day.

The roughest trip includes the “Grim Crawl of Death,” where you crawl through a tight space after rappelling through frigid waterfalls. The average person is not interested in experiencing this adventure, only hearing about it.

Summary of the 5 Deepest Caves in the United States

Here’s a summary of the 5 deepest caves in the United States, where they are located, and how deep they are:

The photo featured at the top of this post is © Ko Zatu/Shutterstock.com