Yes, many of the most famous National Parks in the United States actually began their lives as National Monuments. The primary difference lies in how they are created: a National Monument can be established unilaterally by the President of the United States using the Antiquities Act of 1906, whereas a National Park requires an act of Congress. Because the presidential route is much faster, it is often used to provide immediate protection to a site. Once the area has proven its significance and developed the necessary infrastructure, Congress may vote to "upgrade" it to National Park status to ensure more permanent funding and a broader scope of protection. Historic examples include the Grand Canyon, Zion, Olympic, and Arcadia, all of which were first protected as monuments. More recently, sites like White Sands (2019) and New River Gorge (2020) made this transition. This "promotion" often brings increased tourism, more extensive ranger services, and a higher level of international prestige to the local community.