National monuments are protected areas in the United States designated by the President or Congress to preserve significant natural, cultural, or historical features. These sites can include landmarks, structures, or unique landscapes that hold importance to the nation's heritage. Examples of national monuments include Devils Tower in Wyoming and Machu Picchu in Peru. The purpose of national monuments is to safeguard these treasures for future generations and promote public enjoyment and education. They often provide opportunities for outdoor activities like hiking, camping, and wildlife viewing, while also serving as reminders of the country's diverse history and natural beauty.