The Secret Underground Train Platform: Walking along bustling Park Avenue, you’d never guess there’s a big secret hidden just below your feet. An abandoned train platform, known as Track 61, was originally built to carry freight from Grand Central Terminal just a few blocks away. As the years went by, it was transformed into an underground station for VIPs to enter the Waldorf Astoria in a clandestine manner. President Franklin Roosevelt was the most famous to take advantage of this perk, and there was even an elevator big enough to hold his bulletproof automobile. ...