Did you know that there's a "Top Secret" tunnel at Grand Central Station? In fact, the exact location of this hidden tunnel remains confidential to this day.

This train station is so secret, former MTA officials were interrogated by armed security upon entering the site. The train that traveled on this hidden track was built specifically for Franklin Delano Roosevelt. Because Roosevelt suffered from polio, it had an elaborate suspension system built specially for him to prevent lateral motion.

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The secret train station was originally built so Roosevelt could commute to the Big Apple in stealth mode.  One of the train car's contained the President's limousine that covertly conveyed him to a private elevator. The elevator exit was conveniently located at the luxurious Waldorf Astoria hotel; that way he was able to enter the grand ball room incognito and completely undetected.

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It has been reported that the private train track is still being used by presidents today in the event of an emergency.