Primary Interstate Highways are the major interstate highways of the United States and have a one or two-digit route number. Even (0, 2, 4, 6, or 8) route
Boulder is a city in the state of Colorado, in the United States. It is the county seat of Boulder County. Boulder is in the foothills of the Rocky Mountains
100 of the state's other 104 counties are in. Only four counties (Hamilton, Greeley, Wallace, and Sherman), all of which border Colorado, observe Mountain