Caves are stunning. One minute you’re walking past layered cake, swirls of buttercream the next, and then by sugared icicles that drip gobs of gooey batter.

Okay, I may have been a little hungry when I visited Howe’s Cave in rural New York State. Because despite the colorful lights lining the cavern, I couldn’t stop thinking about how much the limestone looked like icing on a gingerbread house. When we passed a formation nicknamed “The Ice Cream Cone,” I joked with my friends about how it looked good enough to eat. 

But all joking aside, it’s not okay to lick—or even touch—a cave wall. Here’s why.

You can get sick.

In general, you don’t want to lick strange surfaces. They often harbor germs, some of which can be pretty nasty. 

The same is especially true for cave walls. Some people think that nothing can live in caves. That’s wrong. As Jurassic Park teaches us, “Life finds a way.” Even in the darkest, most remote places on the planet, bacteria and other microorganisms can flourish. 

In fact, some caves are home to so-called “extremophiles” or microbes that have adapted to extreme conditions. For example, Lechuguilla Cave in New Mexico is home to rare rock-eating bacteria. Other caves have snottites, which are booger-like clumps of bacteria that hang from the walls or ceiling. 

Plus, there’s bats. And bats poop. Bat poop can contain a fungus that causes a disease called histoplasmosis. You get this disease by breathing in the fungus. And if you’re close enough to touch or even lick the bat poop (gross!!!), you’re probably close enough to breathe in the fungus, too. 

Note: The bats in Howe’s Cave live in the part where humans don’t visit, so there’s no need to worry about getting histoplasmosis there. 

It can harm the cave’s ecosystem.

But touching a cave wall is more dangerous to the cave than it is to you. Cave ecosystems are very unique, and very fragile. Only a few species might live there, and introducing even one more can disrupt the entire ecosystem. And contamination is easier than you’d think. In Howe’s Cave, visitors accidentally brought in tiny spores of moss on their clothes. Now, moss grows around the cavern lights.

Your mouth contains 700 species of bacteria and other microbes. Licking the wall might seem like a harmless prank, but it could introduce hundreds of new germs into the cave ecosystem. These germs might not survive, but it’s better to be safe than sorry. It’s not worth contaminating these special places. 

It’s illegal.

The Federal Cave Resources Protection Act of 1988 prohibits “disturbing” or “defacing” caves on federal land. Several states have similar laws. 

Based on what we’ve said here, I’m going to guess that licking counts as a disturbance. 

And finally…

It wouldn’t taste good.

Someone had to say it. That’s all.

If you want to admire cave icing, do it with your eyes and your camera. These places have taken thousands of years to grow; the least we can do is not disturb them.

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