The 1939–40 New York World's Fair, which covered the 1,216 acres (492 ha) of Flushing Meadows-Corona Park (also the location of the 1964–1965 New York World's Fair), was the second most expansive American world's fair of all time, exceeded only by St. Louis's Louisiana Purchase Exposition of 1904. Many countries around the world participated in it, and over 44 million people attended its exhibits in two seasons. The NYWF of 1939–1940 was the first exposition to be based on the future, with an opening slogan of "Dawn of a New Day", and it allowed all visitors to take a look at "the world of tomorrow".