I was a bit disappointed when I moved to Knoxville to find that the MUP system is rather disjointed. I started cycling in Tucson, AZ, which has The Loop (131ish miles of nice mostly interconnected MUP that circles the city). I'm currently training in the hopes of finding some group rides to join -- I typically have to make laps around the main MUP that goes through the southern part of town to get any decent mileage. If I want more than 25 miles, I'll have to start riding the roads.