What does the letter and number code mean at the top of each marker?
These represent the unique code assigned to each marker to identify it. When the marker program was created in the late 1920s, the letter on the sign usually referenced a specific road (for instance, the letter “E” was assigned to markers installed along U.S. Route 1) and the number differentiated each sign within a letter grouping. Today the department assigns an alpha-numeric code based on what letter is most prominently affixed on current signs in the region where a new marker is to be erected. The number given is the next available one. Please note, however, in a few cases during the history of the program, the same alpha-numeric code was mistakenly assigned to different signs.
