Park officials were notified at around 5:50 p.m. that a significant piece of rock broke off Cable Mountain and hit along the East Rim Trail, knocking down trees and “showering visitors … with smaller rocks, branches and a plume of dust and sand.”
The trail, which was closed at the time, sits approximately 3,000 below the mountain in an area called Weeping Rock.
Visitors were trapped for well over an hour as shuttles were forced to wait for the dust to settle.
Three people were injured, with one being transported to an area hospital. Other people stuck in certain locations because of the rockfall were able to “self-rescue,” officials said in a news release.
Zion National Park ranger and public information officer Eugenne Moisa said at least 19 people were trapped, FOX13 reported.
He added that the rockfall was likely the result of erosion.
One hiker from across the way was able to capture the moment on camera.
Park officials have since closed the Weeping Rock Trail and shuttles to that area “until further notice.”