A natural landmark or a structure or site of historic interest set aside by a national government and maintained for public enjoyment or study. a building, special feature of the land etc that is kept and protected by a government for people to visit. In the U.S., any of numerous areas reserved by the federal government for the protection of objects or places of historical, scientific, or prehistoric interest. They include natural physical features, remains of Indian cultures, and places of historical importance. In 1906 Pres. Theodore Roosevelt established the first national monument, Devils Tower, in Wyoming. They are administered by the National Park Service of the U.S. Department of the Interior