Arkansas

Hot Springs is the smallest national park in the system and the oldest protected federal land in America — designated a federal reservation in 1832, decades before Yellowstone established the national park concept in 1872. It sits not in a remote wilderness but in the middle of a small Arkansas city, also called Hot Springs, where the historic bathhouses of Bathhouse Row line Central Avenue in a grand procession of early 20th-century architecture. The park is the city and the city is the park, intertwined in a way that exists nowhere else in the national park system.