How Public Lands and National Monuments Are Designated
Congress can create a national park, but a president can create a national monument alone, under authority Congress handed over more than a century ago. That difference in process shapes which protections last and which ones get reversed by the next administration.
Published July 6, 2026Federal public land protection in the United States runs through two structurally different processes that often get conflated in public discussion. National parks are created exclusively by an act of Congress, signed into law by the president like any other legislation, which means establishing or significantly altering a national park requires the full ordinary legislative process — passage in both chambers and a presidential signature. National monuments, by contrast, can be designated unilaterally by the president alone, without any congressional vote at all, under authority granted by a 1906 law called the Antiquities Act, which the National Park Service now helps administer for many designated sites.
Why the Antiquities Act exists
Congress passed the Antiquities Act specifically to let the president act quickly to protect archaeological sites and objects of historic or scientific interest from looting and destruction, at a time when Congress itself moved too slowly to protect sites facing immediate threats. The law's language is notably broad — it authorizes the president to designate monuments on federal land containing "historic landmarks, historic and prehistoric structures, and other objects of historic or scientific interest," with instructions that the reserved area be confined to the smallest area compatible with proper care and management of the protected objects.
Presidents from both parties have used this authority far beyond the law's original narrow archaeological framing, designating monuments covering millions of acres to protect broader ecological, scenic, and cultural landscapes rather than a single discrete archaeological site. This expansive use has made the Antiquities Act one of the most consequential and most contested pieces of environmental and land-use legislation still in active use, precisely because it lets a president act alone on a scale that dwarfs what the 1906 Congress that passed the law likely anticipated.
The reversal question
Because monument designations happen by unilateral presidential proclamation rather than by statute, a recurring legal question is whether a subsequent president can undo or substantially shrink a monument designated by a predecessor using the same unilateral authority. The Antiquities Act's text addresses creating monuments but does not clearly address rescinding or shrinking them, and this gap has produced real legal uncertainty, with monument boundary reductions by more recent administrations facing litigation that has not fully resolved the underlying question of how much unilateral authority a president has to undo a predecessor's designation. National parks, by contrast, generally cannot be undone the same way, since undoing an act of Congress requires another act of Congress rather than a unilateral executive action, giving park status a durability that monument status does not automatically carry.
Land management after designation
Once land is protected, day-to-day management responsibility typically falls to one of several federal agencies depending on the designation and its specific terms — the National Park Service manages national parks and many monuments, while the Bureau of Land Management or the Forest Service manages other protected areas, particularly larger monuments where multiple use activities like grazing or limited resource extraction may continue under specific restrictions rather than the stricter preservation rules that typically apply within national parks.
The recurring political fight
Because the Antiquities Act allows large-scale land protection without congressional approval, it has become a recurring flashpoint between administrations with different priorities on public land use, conservation, and resource extraction. Supporters of expansive monument designations argue the law provides an essential tool to protect ecologically or culturally significant land before congressional gridlock allows irreversible development or resource extraction to occur. Critics argue that a tool intended for protecting discrete archaeological sites has been stretched into a mechanism for large-scale land-use policy that properly belongs to Congress, not a single president acting alone — a disagreement about institutional process that has outlasted any particular monument dispute and shows no sign of being resolved by either statute or, so far, definitive court ruling.
Public comment and the pace of designation
Unlike many federal regulatory actions, a monument designation under the Antiquities Act does not require a formal notice-and-comment rulemaking period before it takes effect, since it is issued as a presidential proclamation rather than an agency regulation. Agencies tasked with managing the land afterward typically do solicit public input on the specific management plan implementing the designation, but that process happens after the boundary and the underlying protection are already in place, not before, which is part of why the speed of the Antiquities Act process is both its main practical advantage and one of the sharpest points of criticism from opponents who argue affected communities deserve a voice before a designation, not only after.