On Saturday, the public radio program "A Prairie Home Companion" was broadcast from Flagstaff. One of the featured guests was Ian Frazier, who is a writer for the New Yorker magazine. Frazier gave a monologue on northern Arizona and the Grand Canyon; he hiked the South Rim including the entire Trail of Time, and the Trail of Time figures prominently in his monologue.
The concept of a geoscience timeline exhibit based on Grand Canyon geology was first presented to the Grand Canyon National Park in 1995. For nearly 10 years, Steve Semken has worked with founding team members Karl Karlstrom and Laura Crossey, both of the University of New Mexico, and Michael Williams of University of Massachusetts. These scientists, all Grand Canyon researchers for decades, envisioned turning a Grand Canyon hiking trail into a walking timeline that would represent the magnitude of geologic time.
Frazier's monologue is posted online at http://prairiehome.publicradio.org/