The debate over cairns continues as Yosemite National Park rangers give you the green light to knock them down.
Cairns are rocks stacked on top of each other. In some cases, they are trail markers, but more often than not, someone visiting the trail stacked the stones, and outdoor officials want them to stop.
According to a new post from Yosemite National Park, there are a handful of issues with cairns. First and foremost, they go against Leave No Trace principles. Officials say moving the rocks can disturb small animals, insects, and microorganisms that live under the rocks. Removing rocks could even affect endangered species that use the stones for shelter.
Park officials say if you see stacked rocks, feel free to knock them over. Occasionally, newer trails or hard-to-follow paths will have cairns as marks. In this case, you can leave them be, but park rangers say they’ll handle building them.
Learn more about outdoor etiquette before you visit a U.S. National Park.
