I've been trying to draw a circuit for Florence, Italy, which has some very interesting roads up on the hillside around the Piazza Michelangelo. Unfortunately, none of these seem to loop conveniently back on themselves.
I've designed this one down by the hippodrome instead.
It's maybe a little too narrow in places, and the straights are a bit long. Also, I think I'd run it in the opposite direction (clockwise)
http://www.gmap-pedometer.com/?r=6682081