Bright Angel Trail
The Bright Angel Trail is the least strenuous trail to the bottom of the Canyon from the South Rim, but that still doesn't make it easy.  It's a 9.3 mile walk from bottom to top (in our case).  It took eight hours after we had offloaded most of our pack weight to a mule.  Hoping to beat the mid-day heat, we left camp at 3:30 AM, arriving at the rim at 11:30.