By Bob Blake

If you are confused by the NC highway numbering system, you are not alone. Over the past 75 years our state has undergone at least three revisions!

The automobile became the primary means of travel in the late 1920s and each state began numbering highways. By the end of that decade, North Carolina had nearly 3,500 miles of concrete or asphalt roads. Our state labeled major cross-state routes between cities in multiples of ten, with 10, 20, and 90 east/west, 30, 40, 50, 70, and 80 north/south, and 60 for diagonal routes. Spurs from these major roads had three digit numbers.

During that decade it was also popular to label some roadways as “trails” or named roadways. The names were often carryovers from the pioneer days of the automobile when states had little interest in motor travel. A few common ones included transcontinental routes, such as the Dixie Overland Highway (Savannah, Georgia, to San Diego), the Lee Highway (Washington, D.C., to San Diego), and the Old Spanish Trail (St. Augustine, Florida, to San Diego). By the mid 1920’s, trail associations had named over 250 routes. Today some roads have names and numbers, such as US 74, the 515 mile highway between Chattanooga, TN and Wrightsville Beach NC. it is also the Andrew Jackson highway.

Much support for these named routes came from merchants, restaurant owners and hotel operators along the way. They published guides with very specific directions. Remember, there was NO GPS! They also placed painted signs or catchy insignias on telephone poles, barns, rocks, to mark the route. The goals were to promotion of the road, cities and businesses along the way.

Modern automobiles dictated better roads. President Dwight D. Eisenhower foresaw the need to connect America for social as well as defense needs. He launched legislation for the interstate system, officially known as the Dwight D. Eisenhower National System of Interstate and Defense Highways. As of 2013, it had a total length of 47,856 miles, with upgrades and connectors added continuously.

The numbering system assigns even numbers to east/west directions and odd numerals to north/south routes. The odd route numbers increase from west to east, and even-numbered ones from south to north.

Each state owns and operates the Interstate system with one exception. Special funds built the Woodrow Wilson Memorial Bridge (I-95/495) over the Potomac River.

In addition to speedier and safer travel, the system assists evacuations from hurricanes and natural disasters. In emergency situations, all lanes become outbound. The popular urban legend that every five miles is straight to serve as a potential airstrip in times of crisis is NOT true!