The Pennsylvania Archives holds several hundred road and turnpike maps (many manuscript) dating from the 18th and 19th century, see PA State Archives - Record Group 12.9 . However, the Pennsylvania Department of Highways was not formed until 1903 as a consequence of the automobile. Road surveys and road improvements were begun and described in reports issued by Joseph W. Hunter, appointed the first commissioner. These reports contained photos of improvements and documented expenses, but not maps.

No significant appropriations or plans for highway paved reconstruction were developed until passage of the Sproul Road Bill in May, 1911. Edward M. Bigelow was appointed commissioner in June, 1911, as a consequence of this Highway Department reorganization, with Hunter as deputy. Apparently Bigelow had either more professional management skill than Hunter or was more politically connected. After that, so called 'Sproul maps' were issued periodically to show progress on improving and paving state roads. These were not free road maps available to the public. The distribution was apparently limited to state and county politicians and workers, and perhaps libraries, schools, etc. They were also included in state publications like Smull's Handbook for legislators. The road bill namesake, William Sproul, was a long time state legislator who also served as governor circa 1919-23.

From about 1911 to 1915, detailed county road maps were prepared for each county in the state. Ralph C. Benedict, a highway department draftsman, was involved in the preparation of almost all of them and they are sometimes identified by his name. These county maps and the Sproul state maps used a road numbering scheme developed by the highway department to identify road segments. These road numbers did not form continuous routes.

The large Sproul type state maps continued to be issued at irregular intervals up to around 1940. Beginning in 1925, the state began issuing free tourist road maps. The first of these used 'old state' route numbers. For example, the Lincoln Highway, now Route 30, was Route 1. The William Penn Highway, now Route 22, was Route 3, and so forth. Modern route numbers began to be used with the issue of the 1928 map. The Pennsylvania Turnpike opened in October, 1940, and road maps for it were issued (almost) yearly from then on.

State road maps are important because, like oil company maps, they were a means of advertising for both the state and the governor. They appeared (almost) yearly until the 1980's, when bi-annual issue started. The map images are divided by decade and accessed using the links below. There is an image for most years from 1910 to 2020. For some folded maps, in addition to the cover image link, there is a map image link to show the cartography features. Thus, both changes in map illustration and cartography over the years can be seen.