The Maine Department of Transportation uses the nodal system to identify segments of highways. The node-and link referencing system is based on uniquely defined points on the highway system. Each point is assigned a unique number called a node number. Urban compact lines. Public road termini.
Selected railroad crossings Selected bridges.
Other selected locations necessary to preserve the integrity of the referencing system. Interstate Highways are colored light blue, State highways are colored red, State Aid Highways are colored green and townways are colored dark blue.