Research Tip #6
Highway Corridor Maps
The Archives has 6,000+ highway corridor maps (1942-1987) in Series B1804. These topographic maps were produced on 30" x 54" sheets using photogrammetry. At a 1"=200' scale, individual sheets cover an area of approximately two square miles. The maps were used in planning and designing highways, so geographic coverage is of limited corridors in which highways were later built.
Maps are grouped by contract or project identification number (PIN), and map sheets are numbered within each contract or PIN. There is NO list of maps by location. To search, researchers must find the contract or PIN number AND sheet number(s) using one of four key maps of the state. Key maps are NOT available online.
To locate maps, researchers must:
- Use key maps to find the unique index number associated with map sheets covering desired geographic location.
- Use the legend at the bottom of key map to match index number to contract number or PIN number.
- With the contract number or PIN number and sheet number(s) for locations of interest, maps may be requested for viewing in the Research Room. An online box list is available to assist researchers in requesting the appropriate materials. Photocopies are $3.00 each; scans are $10.00 per map.