For 19th century maps of counties, cities and townships, Historic Map Works http://
The site claims to have over 1.6 million maps online. The front page for the Ohio section says that “… the state of Ohio collection contains 440 atlases spanning 311 years of growth and development (1696 through 2007). Within the atlases are 21,405 historical maps, illustrations, and histories…”. I think you’ll find collections of similar size for every state. Their user base appears to be mainly genealogists. When I’m doing genealogical research I look in the county atlases for township plat maps, which have individual plots outlined, showing owners and acreage.
Now for a quick tour; I’m picking out the oldest county map on the first page of the Ohio maps section – Ashtabula County 1856 – which is the only pre-Civil War map here for counties beginning in “A” or “B”. This is a single map rather than an atlas. I click “Zoomify”, and when the map opens, scroll to the bottom and hit Zoomify again to open it to the maximum, which is the only way I can read the small print.
Note that this map contains section numbers in accordance with the system of land surveying prescribed by the Northwest Ordinance of 1787, although the numbering in this county deviated sharply from the standard of 36 sections per township that was used throughout most of the Northwest Territory. (You can read about that here: http://nationalatlas.gov/articles/boundaries/a_plss.html ).
Unlike plat maps, this Ashtabula map does not show the plots of individual landowners. However, it shows the locations of homes (dots) and the names of homeowners throughout the county, except those living in towns. If I were doing family research, I would use this along with a census to more definitely identify the full name and residence of people I was researching. Locations of roads and streams on these old maps are generally accurate enough to be able to zero in on the same location on a modern map (although streams can be hard to find on many modern maps).
Many 19th century maps contain unexpected information and this one is no exception. The right margin contains numbers of public schools (218); teachers (also 218); and total numbers of students and illiterates. Also a list of all the churches, with property values by denomination, and statistics about agricultural production of the county.
Obviously Historic Map Works is a huge site and great for browsing, but keep in mind it is far from being comprehensive. If you’re trying to locate all the online maps or atlases for a particular county, don’t end your search at Historic Map Works.
Note: I don’t seek or receive compensation for recommending sites.