Some of the best white-water on the South Branch of the Potomac River can be found in the Smoke Hole Canyon.  In fact, Eagle's Nest Outfitters has a trip called the Lower Smoke Hole Canyon Trip that promises fairly steep rapids and enough complications to make paddling interesting.

The Royal Glen Dam Trip is also a very popular stream that contains pleasant scenery and challenging white-water for novice and intermediate paddlers.  This trip is often used as a warm up for the Smoke Hole Canyon Trip.

Eagle's Nest Outfitters can help you with rentals or they can even provide a shuttle for those with their own equipment.  Call them at 304 257-2393 for details April through October.