The rail trail goes from York city to the maryland border which is about 21 miles. We rode 10 miles from york, which is around the seven valleys area, and 10 miles back. Its a really nice ride. Its a flat relatively level surface with lots of places to sit and rest and follows an active railroad track thru the woods and farm land. My only issue is that there are sooo many people at certain spots its kind of annoying. However in other spots its just you and nature. I also saw remarkably little trash laying around(amazing since people are pigs), so someone must come along and pick it up regularly and do maintenance. Kudos on that! You can walk, run, bike, ride horses. no motors allowed, so its a nice quiet day overall. check it out!