Definitely add the Blue Ridge Mountains of Northwestern Virginia.  Skyline Drive offers some of the most spectacular scenic views in this part of the country.  It run 105 miles long and overlooks the Piedmont and the Shenandoah Valley.

Of course, while you're out this way, you'll want to stop off in Washington, DC.  It's always a favorite destination for Linda and me.  We went there again recently, and the WWII Memorial is awesome!!

--Scott