The maps in the United States Digital Map Library were either published prior to 1923, produced by the United States government, or both. Each map is accompanied by information regarding the date of the publication and source. The United States Digital Map Library is providing access to these maps for research and genealogical purposes and is not aware of any U.S. copyright protection or any other restrictions. Please see our Copyright Page for additional information.

1. Our first consideration in presenting useful online maps is to have them readable. The maps should be readable to those folks with lesser quality monitors, and to those who are visually challenged. Therefore, most of our maps are very large.

2. Formats: TIFF files are preferred. Your file will be converted to jpeg, but we prefer to optimize the files here for visual clarity and size. Jpegs should be compressed at the lowest level (highest quality.)

3. All data is free to the public, the United States Digital Map Library will not pay royalties on any submissions. Do not send copyrighted material, unless it is your own, and you include a statement of permission to use, in the document.

4. Any obviously false, malicious, libelous, or copyrighted data will be erased. We retain the right to refuse any submission.

5. Once submitted, the data can't be retracted by submitter.

6. These guidelines are subject to change.