Should you push over these stacks of rocks? Here’s what NPS says

YOSEMITE, Calif. (KSEE/KGPE) – Have you ever passed a tower of rocks perfectly balanced on one another while hiking and felt the urge to knock it over? Depending on where you are, that might not be the best idea.

Officials at Yosemite National Park recently encouraged visitors to dismantle these man-made rock stacks, known as cairns, should they come across them within the park.

According to park rangers, “leave no trace” ethics states that when recreating in wilderness spaces, the goal is to leave no signs of human impact on the land so as to respect the other creatures living in it.

And while the effort and aesthetics of these rock cairns may seem too precious to ruin, oversized cairns are a mark of human impact and are distracting in a wilderness setting.

Officials also say building them disturbs small insects, reptiles, and microorganisms that live on the underside of these rocks.

Not every cairn should be destroyed, though.

An example of a large man-made cairn along a trail on Mont Blanc in the Alps. (Getty)

“When used appropriately, rock cairns are great for navigation, safety, and delineating a new or hard-to-follow trail,” Yosemite officials noted.

Each national park has different rules regarding rock cairns. According to the National Park Service, you’ll likely come across ranger-maintained cairns in Canyonlands, Zion, El Malpais, Hawaii Volcanoes, and Acadia, where they serve as trail markers.

These can appear in different styles. There’s the Bates cairn, which looks a bit like a bridge, and conical cairns, which are more like the towers you would expect to see.

A Bates cairn marks the way for hikers on the Gorham Mountain Trail in Acadia National Park. (Getty)

There are, however, national parks that do not build or use cairns, like Capitol Reef National Park.

If you are planning to hike in a national park, the NPS recommends visiting the park’s website for more information on trails and the signage used.

Regardless of whether the park uses cairns or not — and despite Yosemite’s advice — the NPS says that if you encounter a cairn, don’t disturb it. You should also not build any “unauthorized cairns” or add to existing cairns.

Similar rules apply outside of the national parks. Some places, like Colorado’s Pikes Peak, use cairns to help hikers navigate otherwise difficult-to-mark paths. If you’re uncertain about a cairn, don’t destroy it, and don’t add to it.

If you’re unsure if a cairn is real, officials recommend speaking with a ranger or another hiker, or utilizing a map.