A number of data sources may be employed when researching how the Pennsylvania Railroad interacted with the landscape. These sources include but are not limited to:
- ICC Railroad Valuation Maps
- Sanborn Fire Insurance Maps
- Historical Topographic Maps
- Penn Pilot Aerial Imagery
- PRR Form CT1000 and equivalents
- PRR Employee Timetables
- Telephone Directories
ICC Railroad Valuation Maps
The valuation records created by the Interstate Commerce Commission (ICC) provide detailed documentation pertaining to the railroads of the United States from their beginning until the 1960's. Most of these valuation records were created during the period 1915 to 1920 by ICC and railroad employees who undertook a massive project to inventory almost every aspect of the existing railroad system in the United States.
The valuation maps depict trackage very accurately, but show few buildings or detail outside of the trackage.
Stephen Titchenal's web site, Rails & Trails, provides access to many valuation map sources: http://railsandtrails.com/ICC/default.htm
Sanborn Fire Insurance Maps
The Sanborn Fire Insurance Maps are a valuable resource for genealogists, historians, urban planners, teachers or anyone with a personal connection to a community, street or building. The maps depict more than 12,000 American towns and cities. They show the size, shape and construction materials of dwellings, commercial buildings, factories and other structures. They indicate both the names and width of streets, and show property boundaries and how individual buildings were used. House and block numbers are identified. They also show the location of water mains, fire alarm boxes and fire hydrants.
In the 19th century, specialized maps were originally prepared for the exclusive use of fire insurance companies and underwriters. Those companies needed accurate, current and detailed information about the properties they were insuring. The Sanborn Map Company was created around 1866 in the United States in response to this need and began publishing and registering maps for copyright. The Library of Congress acquired the maps through copyright deposit, and the collection grew to 700,000 individual sheets. The insurance industry eventually phased out use of the maps and Sanborn stopped producing updates in the late 1970s.
The Sanborn maps depict structures very accurately, but are not very accurate for rail trackage.
One caveat: The apparent width of a street is inclusive of any sidewalks. The structure borders shown are the walls and sidewalks are not depicted at all.
The Pennsylvania State University provides Sanborn maps online for the Commonwealth of Pennsylvania: https://libraries.psu.edu/about/collections/sanborn-fire-insurance-maps
The key to Sanborn maps is linked at right.
Historical Topographic Maps
In 2009, USGS began the release of a new generation of topographic maps (US Topo) in electronic form, and in 2011, complemented them with the release of high-resolution scans of more than 178,000 historical topographic maps of the United States. The topographic map remains an indispensable tool for everyday use in government, science, industry, land management planning, and recreation.
Historic maps are snapshots of the nation's physical and cultural features at a particular time. Maps of the same area can show how an area looked before development and provide a detailed view of changes over time. Historical maps are often useful to scientists, historians, environmentalists, genealogists and others researching a particular geographic location or area.
Penn Pilot Aerial Imagery
Penn Pilot, a project sponsored by the Pennsylvania Geological Survey, is an online library of digital historical aerial photography for the Commonwealth of Pennsylvania. You can browse, view, and download thousands of photos covering the Commonwealth from 1937 to 1942 and 1967 to 1972.
The photos were produced by the United States Department of Agriculture, Agricultural Adjustment Administration (now known as the Farm Service Agency).
Penn Pilot is hosted by the Pennsylvania State University: http://www.pennpilot.psu.edu
The image shown is a greatly reduced sample.
Telephone Directories
Telephone directories are a great source of information for who/what occupied a specific address. Remember, addresses are shown on Sanborne maps, and early telephone books usually containes street listings in addition to alphabetical listings.
Public libraries and historical societies are great sources for telephone books.
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PRR Form CT1000 and equivalents
More to come...
PRR Employee Timetables
More to come...