Half of my heart lives in Colorado, so I go there as often as possible. Boulder is an amazing town if you like easy access to nature, drinking microbrews and riding bikes. Valmont Bike Park is in the center of town, and though a little limited, has 3 separate pump tracks, multiple freeride features and a super fast cross country track. Its also conveniently located next to two microbreweries and the county jail, so you can plan your day accordingly.
The brick building in the background is the Boulder County Jail.
Boulder is nestled into the foothills of the Rockies, and the Flatirons mark the western border of town. Follow any canyon up into the mountains, and cross country trails abound. Much like this area, the weather at this time of year is hit and miss. A thick layer of dirty ice covers anything in the shade, while the year round sunshine melts anything it can touch. It snowed twice during my visit, but was melted by the next afternoon. For sheer variety of riding, Portland can't be beat, but if you don't mind some mountain side climbing, the vistas from the Rockies are stunning.
The Flatirons at dusk, as seen from Chautauqua Park.