A Straight Line Diagram (SLD) is a two dimensional graphic representation of the physical roadway characteristics of a highway as if it had no turns or curves. Mileage is based on the centerline of the roadway as measured from the western or southern county line or other true beginning. All routes on the Interstate, U. S. and State Route systems are shown on these diagrams.

All SLD files accessed via this site are current as of January 1, 2009.

Click on the county below to access all the SLD files in PDFs: