ocr: Preserve the Beauty. On March 1,1872, Tellowstone became the first national park in the Jnited States. By1920 there were 15 national parks- -including Alaska's Jenall (forerly Mount McKinley).openedin 1899,andHawail Yolcanoes, 4 openedin1 - 1916.In1916the National Parks Service was created to ensure that - the naturalbeauty of the Jnited States wouldb be oreservedi for future generations to enjoy.