Out-of-Print Topographic Maps
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Federal Government Sites
The US Geological Survey has established a website to download out-of-print maps. There are some 180,000 maps available for download from: Historical Topographic Maps.
All US Geological Survey publicationsmay be downloaded as pdf files. The maps associated with these reports often show details not available on other published maps.
US Bureau of Land Management / General Land Office Surveys (Note only a few states' surveys are available on line, go to the BLM Website and open the link "our offices and centers" for a contact phone number and email address. You will need to know the Township and Range of the survey - each state should be able to provide you with a paper copy. These BLM / GLO cadastral survey plats (and the field notes) are a treasure trove!
Other Links to Explore: