There is an aqueduct that carries water from the St. Vrain Creek near Lyons to the Boulder Reservoir. Unfortunately, the road along the aqueduct is not open to the public for walking, biking, hiking, or driving. This is the 2nd in a series of caches along county roads that cross the aqueduct. There is no need to go past gates or fences that have restricted access. All of these caches are along roads with little traffic, and are good places to road/mountain bike.