According to those two stone pillars, this was the Henry Hudson Entrance for the 1939-40 and 1964-65 World's Fairs held here at Flushing Meadows-Corona Park. You can see two observation towers from the New York State Pavilion in the background.
Here's a map from 1965, with the Henry Hudson Gate (as it's called on the map) located near the bottom left corner.
Day 66
Portal of the day
March 5th, 2012
I remember the Wold’s Fair of 1964. It was a big event and we took the train and ferry from NJ and then the subway. It was an awesome experience for a 12- year old!