Two places I would recommend, one in the winter and on in the summer months.
1. Tuscon AZ "The Loop"
The Loop - Pima County
All paved trails,over a hundred miles of riding..
2. Grand Canyon of the East in Pennsylvania
PA Grand Canyon - Lodging, Attractions, Directions, Maps
Pine Creek trail is a rails to trails project. It is mostly hard packed gravel. I have ridden a road bike on it, but not fun. Bigger tires are recommended.