Book excerpt: "There's the Grand Canyon as seen from one of the rims. Spectacular. Awe-inspiring. Dramatic. And there's the Grand Canyon below the rims, a very different place steeped in wilderness, bus-sized boulders, tumbling streams, knee-shredding switchbacks, solitude, and the cataract-punctuated Colorado River. The trails in Grand Canyon National Park attract more than 80,000 permitted overnight backpackers annually, as well as an untold number of day hikers and mule riders. Join author Seth Muller on a grand adventure, searching for the Grand Canyon's soul along miles of canyon trails. Muller profiles rangers, artists, volunteers, hikers, ultra-marathoners, mule skinners, and others who regularly experience the inner canyon, presenting the Corridor Trails in intimate, creative prose that will carry the reader into the depths of the canyon and back out again"--P. 4 of cover.