New York World's Fair has been held twice in New York City. The first fair opened in 1939. Its theme was "Building the World of Tomorrow," and its symbols were the Trylon (a triangular obelisk 700 feet, or 210 meters, high) and the Perisphere (a ball-like structure 200 feet, or 61 meters, wide). The fair was held in Flushing Meadow Park in Queens. It promoted such inventions as television, nylon, and air conditioning. Scheduled to end in 1939, the fair was reopened in 1940 because of its popularity. It attracted almost 45 million people.