Although this is from a genealogy post of Feb 4, 2019, the Sanborn Maps are a huge help to us. Library of Congress now has 25,000 available with a total of 500,000 to be up in 3 years. Here is an article outlining its use. https://www.familytreemagazine.com/...n1RPujg_wPrmtU6MXX1wj5YTGeQw7UDCedwupYLAJ5G3U