Developments in Highway Signs and Markings

An interesting approach to a study of the development of U. S. stand­ ards for highway signs and markings is along historical lines. The first effective step toward national standardization of highway signs was taken by the Mississippi Valley Association of State Highway Departments in 1922 when the Association appointed a committee of five to study the subject. The Association adopted the committee’s report in January, 1923. The Mississippi Valley standards established one feature of the pres­ ent national standard signs. Distinctive shapes were prescribed for the several classes of signs, viz., a circular railroad crossing sign, an octagonal stop sign, a diamond-shaped warning sign, a square caution sign, rectangular information signs, and a characteristic route marker to be designed by each state. All these signs, with the exception of the route markers and the rectangular information signs, were to be 24 inches across. All of them were to be white with black lettering and border. This initial step by the Mississippi Valley Association greatly speeded subsequent progress toward national uniformity. Within a year Indiana, Minnesota, Wisconsin, Michigan, and Ohio started erection of signs conforming to these standards on their state highway systems and several of the other states were planning to do so. A situation created by the activities of numerous “trail associations” in promoting the marking of sundry and miscellaneous routes led to the adoption of a resolution by the American Association of State Highway Officials at its meeting in 1924 requesting the Secretary of Agriculture to appoint a board to select and designate a system of interstate routes and to devise a system of numbering and marking the highways of that system. In 1925 the Secretary of Agriculture appointed a Joint Board on Interstate Highways with 21 members from state highway depart­ ments and three from the U. S. Bureau of Public Roads. The Board made its report in October of that year, covering the proposed system of U. S. Highways, the route-numbering system, and a comprehensive set of sign designs based for the most part on the Mississippi Valley stand-