There are more than 420 sites in the US National Park System, but only 63 carry the headliner -- capital N, capital P -- "National Park" title.
원문출처 : https://www.cnn.com/travel/article/least-visited-us-national-parks-2021/index.html
원문출처 : https://www.cnn.com/travel/article/least-visited-us-national-parks-2021/index.html