Best driving roads I have found in this country, in no particular order.
US 421/119, Southeastern Kentucky, running from 1000-4000 feet through some of the most beautiful and technical roads you can drive.
Taconic Parkway, NYC to MASS Border. This road just rocks. Great scenery, good driving, well maintained, fast, technically good at speed.
Taconic State Parkway
Virgin River Canyon, I-15, Vegas-St. Georges UT. This also is a good road. Best run at 100+ with Ballad for a Girl from Buchanan [Chicago 2] on the stereo.
Mulholland Drive, SoCal. It has history, curves, scenery, cops, more hot cars than you can imagine. Best in a quick car or a hot bike. Late night racing is pretty much over. I miss my youth.
Tail of the Dragon, US129 on the NC/TN border. 318 curves in 11 miles. Wear gloves. Don't go on weekends. The noobs and cops will wear you out. In the spring and summer the cops bring everything including choppers and haulers. They mean business. Best time is 10am on a Tuesday. Dew is off the road and weekenders are home telling their tales.
Tail of the Dragon at Deals Gap and Cherohala Skyway, Graham Co, NC
I-70 out of Glenwood Springs Colorado heading East. Really cool road with great scenery, very good roads, good cuts, great to exercise a well tuned car.
I-70, UTAH between mile markers 80-110. Both the drive and the scenery are just awe inspiring. Don't forget to stop at both rest stops.