Instead of going back the way I came, I went down the back side of HuaynaPicchu to see the Gran Cavern….didn’t really think about how long that would make my last hike – it was close to 4.5 hours after already doing the Inca Trail.  It was easier, though, because it was at only around 7,000 feet above sea level and the back side of the mountain was not crowded so it was very peaceful.