Last month geologists published a paper in the journal Science that concluded the Grand Canyon -- or at least part of it -- is much older than most researchers think.
The study reopened a contentious debate among scientists. And it got reporter Laurel Morales thinking about the magnitude of the Grand Canyon’s history.
On a recent crisp, and perfectly silent evening, she takes us to the canyon’s south rim to walk the “Trail of Time” -- a path that encourages visitors to ponder the mystery.