Cinder rock trail, well maintained. VERY flat, but great views and easy riding. This trail is utilized in the wintertime as a part of one of the most epic mountain bike races in the lower 48 called the Triple D Winter Race. Triple D stands for Dubuque Dyersville and Durango, three downs located along the trial. The race only has a 30% completion rate! In the summer time the trail is great for recreational cyclist, but expert mountain bikers will want to contact the chain reaction cycling club for access to private single track in the area.
Heritage Trail is a "Rails to Trail" that stretches across Dubuque County. It can be accessed from one of about 10 trail heads. See: http://www.dubuquecounty.org/Conservation/HeritageTrail/tabid/193/Default.aspx for up to date information.
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