The Iron Mountain Trail (#301) runs the length of the Mount Rogers National Recreation Area from Damascus, VA to Fries, VA following a historical alignment of the Appalachian Trail (i.e great singletrack!). Most of the segments are open to mountain bikes, although there are some notable gaps in the IMT, particularly east of VA 16. These missing segments can be connected with the Virginia Highlands Horse Trail (#337), which runs parallel to the IMT.
This segment is a no-nonsense singletrack through a dense forest in a little-used part in the eastern half of the Mount Rogers National Recreation Area. The area is probably more popular with equestrians than bikers, so be on the lookout for horses, but don't let that scare you off.
The trail is heavily forested so aside from the occasional break in the forest you won't have much to see but the long, winding singletrack in front of you.