Several years ago, we had a memorible trip down the Grand Canyon. Flew into Marble Canyon (F41) now paved..The Sparks Family ran the concession there with overnight accomodations.  They sponsor raft trips down the Colorado, 3 and 10 day trips.;  We took the 10 dayer thru Class 4 & 5 rapids to Lake Mead.  Spectacular scenery, side trips to Suipai pools, Pre-Cambrian rock formations, good food enroute. If you have the time and inclination it's definately a 10 trip, a 10+ for father/son deal.   We were choppered back and forth, another plus...Hope it's still available... 928-355-2225  Don Skeele