This was an anticipated summer revisit to finalize my scouting trip from last fall. My early assessment was dead on. This is a very nice canyon in the late summer. Lots of fresh clear water, and lush vegetation. On this trip I accessed the lower canyon with my mountain bike from old jeep trail that follows the south rim (see map). Using the posted trailhead is a much better package deal, but this option is quicker and more direct if you're somewhat ambitious. The south rim is also a good alternate return route when hiking the entire canyon.
Warning: This is a remote seldom-visited canyon. Black bear and mountain lion frequent the area.
Note: Decommissioned Gaging Station (Hell Canyon #09503720 1965-1972)