Correct me if this has changed, but the nearest velodrome is in Colorado Springs. It is a seasonal track since it is an outdoor track. It was built in the early eighties for the Olympic Training Center before the Los Angeles Olympics in 1984, and at the time it was as smooth as a baby's butt, and really fast because it sits at 6000 ft elevation. Lot's of Boulder riders come to ride here, so car pooling is always a good idea.