What's cool about this jump is that you have to hike behind the roaring Havasu Falls on the other side of the swimming area. The Falls are your back drop, and the mist makes for a great shot.
The only way to get there is to backpack eight miles towards the Colorado River from the Supai Indian Reservation. Take Route 66 East from Kingman and you'll hit it. Careful, the roads are under jurisdiction of the Tribal Police, and any speeding tickets have to be brought before the Chief.
The top of the waterfall is definitely jumpable, but the Tribe fines you $2,000 if they catch you jumping off of it. Too many yahoo's get drunk and try to jump off of it and don't know what they're doing and have to get life-flighted out. Indian legend has it that the Supai Braves would jump off of it to prove their Manhood. If you've never been down there, you'd love it. Well worth the trip.