Centerline miles measure the length of a road or highway regardless of how many lanes it has. Because of divergences and curves, centerline miles can vary slightly between the two sides of a divided highway. Centerline miles are a more intuitive measurement of the overall length of roads than lane miles. (For instance, if there are only 10 centerline miles of roadway in a given city but it all consists of five-lane highway, it would measure 50 lane miles.)

Centerline Miles illustration

Illustration: Centerline Miles

 

Centerline Miles photo

Source: The illustration above represents what the public will see on our highways as Centerline Miles.