Ridng a mule into the Grand Canyon can be a transformative experience for many people. All conversation stops in the first 1/4 mile when people realize they are in the land of the vertical and their lives are being trusted to a mule they just met. There is a reason mules are used instead of horses.
It takes at least 3 1/2 to 4 hours going downhill to reach the river at Phantom Ranch. The normal trip on Bright Angel Trail, will have people spending the night there and returning the next day which takes longer than the trip in. There is a strict weight limit for the trip which used to be 190 pounds with all your clothing. The faint of heart should not apply.