National Parks vs National Monuments

A National Monument in the United States is a protected area that is similar to a national park (specifically a U.S. National Park) except that the President of the United States can quickly declare an area of the United States to be a national monument without Congressional approval. National monuments receive less funding and afford fewer protections to wildlife than national parks.

Another difference between a national monument and national park is the amount of diversity in what is being protected; national monuments aim to preserve at least one unique resource but do not have the amount of diversity of a national park (which are supposed to protect a host of unique features)

Someone suggested that Parks are designated by the President/Executive Branch and Monuments by Congress

A National Monument in the United States is a protected area that is similar to a national park (specifically a U.S. National Park) except that the President of the United States can quickly declare an area of the United States to be a national monument without Congressional approval. National monuments receive less funding and afford fewer protections to wildlife than national parks.