Map of Old Mexico City
This map is the work of Juan Gómez de Trasmonte and represents Mexico City in the 17th Century. Mexico City is the capital of Mexico and is also known as the Federal District, Distrito Federal in Spanish, which is the reason D.F. follows the official name of the city.
Mexico City is an area of Mexico known as both the Valley of Mexico and the Valley of Anáhuac. This area is in the center of Mexico in the high plateaus with an altitude of 7,349 feet. The municipality officially became known as Mexico City, Ciudad de México, in 1585, before which it had been known as México Tenustitian since 1524.
Public Domain
Public Domain is a copyright term that is often used when talking about copyright for creative works. Under U.S. copyright law, individual items that are in the public domain are items that are no longer protected by copyright law. This means that you do not need to request permission to re-use, re-publish or even change a copy of the item. Items enter the public domain under U.S. copyright law for a number of reasons: the original copyright may have expired; the item was created by the U.S. Federal Government or other governmental entity that views the things it creates as in the public domain; the work was never protected by copyright for some other reason related to how it was produced (for example, it was a speech that wasn't written down or recorded); or the work doesn't have enough originality to make it eligible for copyright protection.