All of our road trips always go through GATLINGBURG TN and the SMOKY MTNs Park. We also love the SHERANDO Camp in the I81/I64 area near Waynesboro VA. Another great campgound is on I59 south of Chattanooga at the Trenton GA exit called CLOUDLAND CANYON... We love the high country style camping around the NATL FOREST areas.
Have not made many trips above the Virginia Line areas but PA has some great high country campsites. Camping in the high country near Thurmont MD US15 and the Catoctin Mtn area is on our list to do...
We too also like to use the GOOGLE MAPS - just type in CAMPGROUNDs in the search window and it will show them as you move along the roads... You can actually zoom down and see the campgound layout if you like.
Roy and Carolyn