Although technically, this is a bike path, there are extended sections of singletrack that dart in and out of it with some surprisingly technical spots. For maximum singletrack/pavement ratio, start just south of the Holly intersection and look for the little paths that drop off the pavement towards the river. This place can get really busy so ride friendly! For people who live in Denver, this is an awesome place to go after work and hone your skills and have some fun, plus you can ride it for all but three or four months of the year. I'm rating it as a 7 with the caveat that this is the highest rating I could ever give a city ride.