The US National White Water Center is hands down on one of the best destination in the Charlotte area!. A most visit place if your in the area of traveling for business. I probably come here at least 4-5 times a month to take advantage of their extensive mountain bike trail network. The rafting is enjoyable as well, but i've only down this once.
A yearly parking pass is a must, which cost $40 for an entire year, and well worth the price (the daily parking fee is $5 per car). The onsite bar/restaurant is OK, nothing special but they always have a decent beer selection with rotating taps. plenty of local Charlotte Brewery to choose from (Noda, Triple C, Old Mech, etc....)
Bring the family and go spend your entire day there - you'll be glad you did!