The ‘very’ earliest county map is the 1687 map of Thomas Holme, A Mapp of Ye Improved Part of Pennsylvania in America divided into Countyes Townships and Lotts. This map showed the counties of Philadelphia, Chester, and Bucks, the founding counties of the state created in 1682. However, it and the subsequent maps of Philadelphia during the 18th century fall more into the state or city, rather than county, category.

County maps of the 19th century are listed below. The earliest county land ownership map is A Map of Wayne and Pike Counties, prepared in 1814 by Jason Torrey, and considered the first such map ever made in the United States (see Couzen in Wolter & Grim). The map, shown here in a Library of Congress copy , was accompanied by a pamphlet titled An Index to the Map of Wayne and Pike Counties, which listed the land owners identified only by number on the map.

In March 1816, the legislature passed an act “for the formation of a map of each of the counties within this commonwealth.” Completed from 1816 to 1820, these maps were based upon actual county surveys with township boundaries, roads and distances, post offices, mills, factories, iron furnaces, iron forges, churches. Deputy surveyors did most of the work and a clerk in the Land Office, the first of whom was John Whiteside, made office copies of these for the Surveyor General; so they are sometimes called the “Whiteside Maps.”An example of a Whiteside map is this image of Centre County. These county maps were used to create a definitive state map under the direction of John Melish, which was published in 1822. Melish entertained the grand idea of creating a state atlas presenting all of the county maps and entered into an agreement in April 1821 with Philadelphia engraver Benjamin Tanner for publication. However, few of the county maps were ever engraved and published, probably due to Melish’s death in 1822. The original surveyor maps were never returned to the Surveyor General and today the State Archives has only the Whiteside copies. Forty-four of these manuscript county maps are preserved in the archives and are included in the list below. Some are accessible at libraries in photographic reproduction and scanned images of all are available at the Pennsylvania Archives.

In 1822, Melish published a catalog of maps for sale; eight county maps are listed: Philadelphia, Montgomery, Chester, Berks, Dauphin and Lebanon, Huntingdon, Somerset, Wayne and Pike. The Philadelphia county map published by Melish is reproduced in Ristow on page 114. For more on the Melish state and county maps, see Babinski.

The classic county wall maps were published from around 1850 to 1870. They were a direct precursor to the county atlas. However, not all the maps after 1850 listed here are, strictly speaking, wall maps. Also, some maps after 1860 titled 'Oil Region' may show more than one county and probably deserve a category of their own. The many county maps prepared circa 1880 as part of the Second Geological Survey are not included. The list was compiled from the holdings of the Library of Congress, the Pennsylvania State Archives, and internet library searches. Most of the maps listed below, as well as others, can now be seen at the Pennsylvania State Archives website on maps. This page has been updated with additional links by Penn State Library.