Backpacking Guides and Trips in United States

There is a secret to a Grand Canyon rim-to-rim hike: Take four days to do it, even if you can do it in one. I have friends who go South to North in one day, then North to South the next. But how much of the Canyon do they really get to see? How much time can they spend at Ribbon Falls? It's a destination unto itself. Can they spend a couple of...