After driving several hours across the Indian reservation,  now for a time with the canyon in full view,  I felt near it's edge.
Anxious to take a closer look, I turned off the dirt "road," cautiously driving directly at it.  Sensing my goal was reached,
I stopped to hike ahead. Surprisingly just a few yards more, and I was looking straight over the edge! 
Peering out in awe,  as a tour plane passed through the abyss, breaking the eerie silence.