We drove entire length of Skyline & Blue Ridge last fall & enjoyed it. BUT would not do it in the RV again. Would use RV to camp off the parkways & use toad to drive the parkways. First, you can not let your mind wander (ie your RV wander), or you will almost immediately be drifting off the road or across the center. We have 33 foot pusher, pulling a GMC Canyon, & max height of 11ft 6in. speed limit is from 35 to 45, but you rarely do it, road is too curvy to maintain speed, or you braking going down hill or trying to regain speed up hill. Worst part for us was that there is little or no parking for RV with tow at overlooks, & even at visitor centers! Twice we had to park on grass, & once park half mile down road & hike back. Our drive was during work day in fall, with school back in session, so it was not busy. Would not recommend making this drive in 40 footer at height of tourist season. The shortest tunnels (& the most tunnels) are in NC; believe the heights listed in Nat'l Park info & don't count on driving in middle of tunnel unless you like to play chicken. Bigger problem is that park service has not trimmed trees, so we kept getting whacked with tree branches on the side of RV. anything over 12 feet might get roof damage (but only guessing here). Almost no camping on parkways, do your research to locate campsites in advance. We found info from VA & NC info centers to be almost useless for RV parks-- info is centered on motels. Lastly find out how RV park recommends you drive there. We turned off parkway onto state road to RV park & barely saw a sign that said No Semis Allowed & Not Recommended for RVs! We continually had to cross center line to make hairpin turns. RV park owner stated many an RV'er had burned up their brakes. Bottom line was that we stayed on both Parkways because they were NOT busy & driving conditions did not bother me. If it had been busy, we would have given up. If you can only make drive with the RV, then give yourself plenty of time & do it; it is well worth the effort! - corrie & dan ps - in our opinion, Natchez Parkway is a freeway compared to these Parkways.