3. Whispering Gallery, Grand Central
Got a secret to tell? The acoustic pockets of the Guastavino-tiled vaults in the Grand Central Terminal‘s Whispering Gallery act as the perfect pathway for messages. Just stand with a partner at opposite diagonals of the base and talk into the arches. Whispers will be heard across the distance as if you and your partner were standing right next to each other.
As we mention in our popular Secrets of Grand Central article, nobody knows whether this whispering gallery was built this way on purpose, but it has provided endless amusement for residents and tourists alike.