This was America’s first official National Monument.
The Devil’s Tower
Mount Rushmore
Rainbow Bridge
Little Bighorn Battlefield
The Devil’s Tower, Wyoming. In 1906, Theodore Roosevelt declared the rock formation to be the first National Monument. He used the Antiquities Act which allowed him to put under special protection "historical landmarks, historic and prehistoric structures, and other objects of historic or scientific interest that are upon lands owned or controlled by the United States as National Monuments."