A National Monument in the United States is a protected area that is similar to a National Park, but can be created from any land owned or controlled by the federal government by proclamation of the President of the United States.
National monuments can be managed by one of several federal agencies: the National Park Service, United States Forest Service, United States Fish and Wildlife Service, or the Bureau of Land Management. Historically, some national monuments were managed by the War Department.
National monuments can be so designated through the power of the Antiquities Act of 1906. President Theodore Roosevelt used the act to declare Devils Tower in Wyoming as the first national monument.
The Antiquities Act of 1906 resulted from concerns about protecting mostly prehistoric Native American ruins and artifacts (collectively termed "antiquities") on federal lands in the American West. The Act authorized permits for legitimate archaeological investigations and penalties for taking or destroying antiquities without permission. Additionally, it authorized the President to proclaim "historic landmarks, historic and prehistoric structures, and other objects of historic or scientific interest" on federal lands as national monuments, "the limits of which in all cases shall be confined to the smallest area compatible with the proper care and management of the objects to be protected."