This was followed by the formation of the National Park Service in 1916. As of January 2021, there are 130 National Monuments that are managed by various federal agencies. From New York's Statue of Liberty to California's Muir Woods, these monuments are as diverse as they are beautiful.

As of early 2026, the United States has 138 national monuments. These are protected areas established either by an Act of Congress or, more commonly, by a Presidential Proclamation under the Antiquities Act of 1906. National monuments are distinct from National Parks in that they often protect a specific historical, cultural, or scientific resource (like the Statue of Liberty or Devils Tower) rather than a broad, diverse landscape. They are managed by various federal agencies, including the National Park Service (NPS), the Bureau of Land Management (BLM), and even the U.S. Forest Service. The number of monuments can change relatively quickly at the discretion of the President; for instance, the 2020s saw significant expansions and new designations focused on civil rights history and marine conservation. While many monuments like the Grand Canyon were later upgraded to National Park status, the current list of 138 represents a vital part of the nation's heritage, covering millions of acres of both land and sea across the 50 states and U.S. territories.