I try to visit as many different bike trails as I can while driving around the country. I especially like the Rail-Trail system, which tend to be flat, since they are built on land formally used by trains. Part of my regular daily commute takes me over a large bridge on the Ohio Turnpike over the Cuyahoga River. If you look north down river, you can see part of the Cleveland skyline about 20 miles away. If you look below, you can see a trail alongside the river. That is the Cuyahoga section of the Ohio & Erie Towpath Trail. While I don’t think it is technically a rail-trail, it is paved, and fairly flat and easy to ride. In the winter, the trail is used for cross-country skiing. Earlier this Autumn I parked the truck at the Pilot Travel Center in Richfield, Ohio, about five mile to the west, and rode to the trail. The roads to the trail are safe to bike, and very scenic, but very hilly.
I only had time to explore a small portion of the trail, but I’d like to someday ride its entire legnth beginning in Cleveland.