Pennsylvania seems to take care of most gravel roads too well to use a skinny tired road bike on them. Had some bad experiences waiting for people fixing flats. Nothing worse than a well-maintained gravel road with fresh gravel. Give me one that hasn't seen any maintenance for 10 years, much better. One trick they seem to have started using a lot is taking a road grader along a road to uncover the gravel they put down in the past. It can be like riding on ice.