United States. Post Office Dept. "Post route map of the states of Maryland and Delaware and of the District of Columbia showing post offices with the intermediate distances on mail routes in operation on the 1st. of September, 1897." Map. Washington?: The Dept., 1897. Norman B. Leventhal Map & Education Center, https://collections.leventhalmap.org/search/commonwealth:7h14b522q (accessed May 09, 2024).