A new chapter to Grand Canyon National Park's geologic past has come to light in the unique form of two sets of fossilized tracks more than 300 million years old that are lying in view of any hiker on the Bright Angel Trail. Those tracks, according to paleontologists, "are by far the oldest vertebrate tracks in Grand Canyon."
“They literally are on the edge of the trail," Stephen Rowland, a University of Nevada Las Vegas palentologist who studied the tracks, said Thursday morning from his office. "I talked to the trail crew chief, and kind of the myth was that they had fallen on the trail and the trail crew had moved them off, but he told me that that rock is sitting right where it fell. They didn’t move it at all.”
https://www.nationalparkstraveler.org/2020/08/update-grand-canyons-prehistoric-past-appears-313-million-year-old-tracks