List of proposed National Monuments of the United States
The President of the United States can establish a national monument by presidential proclamation, and the United States Congress can by legislation. The Antiquities Act of 1906 authorized the president to proclaim "historic landmarks, historic and prehistoric structures, and other objects of historic or scientific interest" as national monuments.
In a 2010 "Not for Release" - memorandum by the United States Department of the Interior 14 areas were listed in the "Prospective Conservation Designation" attachment as "good candidates for National Monument designation under the Antiquities Act". These areas are included in the list of proposed National Monuments in the next section and marked with a blue-green background.
In subsequent attachments in the same draft "areas worthy of protection that are ineligible for Monument Designation and unlikely to receive legislative protection in the nearm term" and "cost estimates" of "high priority land-rationalization efforts" were listed.
Some areas have been proposed as a National Monument earlier, but are no longer eligible to be listed above, because they are protected somehow now, e.g. as National Monument, National Park or Wilderness Area in the National Wilderness Preservation System. Some reasons for nevertheless keeping them in the following list might be:
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