We like riding our trikes on asphault trails, because we don't have suspension on our trikes. Most trikes and bikes don't have suspension, so our vehicles are representitive in that regard. So a smooth asphault or concrete trail rates high on our list, while dirt, mud, rock, gravel, shale rates lower due to dustyness, and also usability after a rain. Also of interest to us is where does the trail run? Does it run next to a beautiful river with lots of shade trees, or does it run next to a busy highway, with lots of nasty smelling diesel truck exhaust and lots of vehicle noise? Next to the stream ranks much higher than along the noisy stinky highway. Another factor is where is it located? Do I have to load my trike up in my car and drive 25 miles one way to get to the trail, or can I pedal a few blocks from my house to get to the trail? Is the trail well maintained or are there lots of large potholes, cracks, or heave bumps made when the earth freezes and thaws repeatedly? Also of interest is whether the trail is safe or dangerous to ride from the prospective of potentially being victimized? Do the police patrol it or ignore it? Can I use the trail to run errands from my home to the store? How about the sidewalks? Do they have ramps on the corners, so I can ride on the sidewalks to get to the trails or to the stores to run errands?