The Johns Hopkins University hosts this map collection of Pennsylvania.

"Surf Your Watershed"

Maps with descriptions and commentary from the 17th through 20th centuries.

Twelve maps from the 1700s, 1800s.

Find maps of cities, crops, wind directions and other references.

The Perry-Castañeda Library Map Collection.

Pennsylvania's official geospatial information clearinghouse and the Commonwealth's node on the National Spatial Data Infrastructure (NSDI).

Map includes interstate and U.S. highways plus major cities and towns.