What are topographic maps and where can I get them?
Topographic maps are special in that they show the shape of the earth’s surface by means of contour lines. Contours are imaginary lines used to connect the points that have the same elevation on the land surface. The lines are separated from each other at regular intervals, for example, at every 20 feet of elevation. The patterns and spacing of the topographic contours allow one to visualize the shape and relief of the land surface anywhere on the map. The maps also enable one to determine the surface elevation at a given locality. However, topographic maps also show many other useful features such as roads, railroads, streams, lakes, buildings, cities and towns, county and municipal boundaries, and forested areas—to name a few. The U.S. Geological Survey prepares topographic maps of Pennsylvania at various scales in cooperation with the Pennsylvania Geological Survey. The most commonly used topographic maps are the 7.5-minute series, which have a scale of 1 inch equals 2,000 feet or 1
