The C&O Towpath is more like "pounded peat" than like a contemporary graveled rail trail built by a park district. A friend of mine crashed on a remote section of that towpath when he rode through a pothole disguised under a path of leaves. Gashed his hand.

If I was riding through Ohiopyle, I would stop at the gravel apron and watch the kayakers surf at Swimmer's Hole on the lower Yough. It is a few miles downstream from Ohiopyle (before you get to town). The park marks each rapid with posts with two letter designations. Look for SH (I think). It is the only gravel apron I recall. You will have to leave your bicycle and trundle down the slope to watch the boats. There's a lot on weekends and many fewer on weekdays.

If I were in Ohiopyle, I would go see the waterfall. I would not like riding off the trail there. That is where the Youghiogheny River cuts through Chestnut Mountain and Laurel Mountain and all the roads are steep and twisty. The drivers are not the best. There is a new motel in Ohiopyle and rooms at Falls Market. The campground at Confluence is nice.

The only bad segment of the Allegheny Highlands Trail is at the Pinkerton Notch before Rockwood--rough gravel. The view out of Savage Mountain tunnel over the Cumberland Gap is magnifico. They even put up park benches so you can stay a while. I have seen some people pitch a tent at the tunnel. I could dig watching the sunset and sunrise from there. A lot.