Quick: What New York City park was F. Scott Fitzgerald referring when he wrote of the valley of ashes in “The Great Gatsby”? In what park can the Unisphere—a 12-story-high, spherical representation of the earth and a remnant of the 1964 World’s Fair—still be seen? And what park hosts the Stark expo in the film “Iron Man 2”? By now you’ve probably gathered that all three places are one and the same—Flushing Meadows Corona Park in Queens. The park itself …More