There is significant climbing on the 100 route. But its a great route, quite possibly the best mountain event in NC as you ride the most scenic area of the Parkway. I usually ride the metric, and its plenty nice. I just rode the Ring of Hades with BikeWNC a couple weeks ago and, it includes most of the second half of the Tour de Tuck century. I believe Charleys Creek has one section that is about 18%. Ouch!

The other routes on Motion Makers website also have plenty of climbing. Tour de Cashiers is the toughest event up that way, imho, though I've only ridden the metric. But its a humdinger and the full century includes the climb up Walnut Creek.

You also need to sign up for the upcoming Tour de Nantahala and, Tour de Franklin events. Both are outstanding.