The Automobile Blue Book (1901–1929) was a pioneering American road guide series for motorists in the United States and Canada, best known for its detailed point-to-point driving directions in the years before numbered highways.
     NOTE: Wisconsin became the first state to number its highways in 1918.

Created by Hartford automobile enthusiast Charles Howard Gillette, the first edition (1901) covered 62 routes between major northeastern cities such as Boston, New York, and Washington, D.C. Originally intended to link automobile supply stations and provide repair advice, the guide soon focused on intercity travel and trip planning.

In 1906, the American Automobile Association (AAA) began sponsoring the series, greatly expanding its reach. By 1907, maps were included and maintenance tips dropped in favor of advertisements and touring information.

Before 1927, each volume provided detailed turn-by-turn directions between cities, often using landmarks instead of compass bearings due to the lack of standardized signage or continuous roads. These routes emphasized scenic interest and practical stops over the shortest distance, and by the 1910s the Blue Book had become “the standard publication” for American motorists exploring an emerging national road network.