Drive south on NC 281 near Sapphire and right before you hit the SC border you should see a sign for Whitewater falls parking (cost is $2). The falls is usually listed at about 411 feet and the hike is 1/4 mile.
Whitewater is claimed by many to be the highest waterfall east of the Mississippi River. I'm not sure if that is true or not but it has to be atleast close. You can just look at the picture and tell how powerful it really is.
The trail to the first observation area is paved and very easy. There is a set of stairs that take you down to another observation area for an even better view. From here you can hike on to the Foothills trail or go left and make your way to the base. I didn't make it to the base that day but hopefully another time.
Once you have seen North Carolina's highest waterfall you can venture south a little ways and see Lower Whitewater Falls in South Carolina. It is an impressive 200 ft tall and about a 2 mile hike.