Q: Engine Bob, is there any truth to that old story about a secret train platform beneath the Waldorf-Astoria hotel that Andy Warhol gave a party on? Or is this just urban legend?

A: Actually, the story’s true-a good portion of it, anyway. You’re referring to what Grand Central maintenance crew (and Metro North brass, though I doubt they’d tell you much about it) knows as “Track 61.” Now, of course, if you’ve ever paid any attention to Grand Central’s numbered gates, you know that there is no Track 61. But that’s part of the idea: The secret platform was never meant-yesterday or today-to be found my members of the general public. But if you want a sense of where it is, say you were to stand on Track 24 (with your back facing the concourse) and look northward; the secret platform would lie dead ahead of you, up below 50th Street. Track 61 is technically part of the Terminal’s hidden lay-up yards that stretch between Lexington and Park Avenues, running from 48th to 50th Streets.

The story of Track 61 requires a bit of background. The tracks approaching Grand Central ran at ground level until July of 1903, when the New York Central Railroad commenced the incomprehensible project of lowering everything underground and, eventually, constructing all of lower Park Avenue on top of it. The project took ten years and ended, in 1913, with the opening of a new Grand Central Terminal (that’s the one we have today, which happens to be the third to occupy the spot.) Most all of the buildings occupying property between Lexington Avenue to the east and Madison Avenue to the west; and stretching between 42nd Street on the south and 50th Street on the north-are literally built on stilts. Tracks thread themselves around steel pilings that hold up the buildings, all of which paid the railroad for “air rights”-meaning, they paid for the right to float above the Central’s trackage, holding no deed for actual earth. (Damn, the things lawyers can come up with.)

One of the buildings built in the New York Central’s “air” was the Waldorf-Astoria hotel, which began rising above the tracks in 1929. Recognizing the strategic importance of its location, the hotel had a short, cement platform installed astride one of the tracks that passed through its basement. This became Track 61, an exclusive platform for the Waldorf’s use. From the start, it was intended as a way for dignitaries (who, in those days, always arrived by train and most often rode aboard a private railroad car) to get in and out of the hotel discreetly, avoiding the flashbulbs of press photographers. An elevator rose from Track 61 up into the core of the Waldorf itself.

Among the first to use Track 61 was General John J. Pershing, who visited the city in 1938. But the secret platform’s most famous (and probably most grateful) patron was FDR. While members of the press corps were aware that the President was paralyzed, it followed an unwritten (and amazingly, never breached) agreement not to mention the fact in print, nor use photographs of FDR using his leg braces or his wheelchair. Nevertheless, discretion had its merits and, for security reasons alone, a private and secure means in and out of Manhattan made plenty of sense for a wartime president. Arriving in the private Presidential railroad car-often arriving from his boyhood home in Hyde Park, just up the Hudson Line-FDR and his entourage would pull up to Track 61, alight, and take the elevator straight up to the hotel’s Presidential Suite. It must have been something to see.

With the passing of years and the coming of air travel, the need for Track 61 diminished (FDR was, however, the first President to use a private plane for executive travel, though the name “Air Force One” would not arrive until, I believe, the Kennedy Administration.) Ironically, the “secret” platform would next be used for two very public events. In 1946, the New York Central Railroad showed off its new 6,000-h.p. diesel locomotive in a PR event it called its “Debut at the Waldorf,” pulling the new engine up to Track 61 for a photo op. And then-yes, finally-there was the Andy Warhol party. That was in 1965 and, in classic Warhol style, the party was themed and named: The Underground Party. Fitting, if nothing else.

And there, the record of the secret platform pretty much ends. Many stories and much mystique have arisen since then, including the tale that the Waldorf kept a freight car down there stocked with surplus china (this was actually confirmed by a friend of mine who worked for the Waldorf for many years, though I never pressed for more details.)

The quest for Track 61 has also become a holy grail for many urban explorers (a successful visit is described in the book “New York Underground,” by Julia Solis.) But, post-9/11 security concerns being what they are, even these fearless souls seem to have realized that a glimpse of a dark old platform served by a rusty elevator is not worth the handcuffs that invariably come with being apprehended in the act.

But if you’d like a risk-free way to get close to the secret platform-and you’ve got some time to kill before catching your train and are profoundly bored-check this out: If you make your way up Park Avenue to the Waldorf-Astoria, walk beneath the awning to the corner of 50th (you’ll be facing St. Bart’s), make a right, then take three steps and look on your right. You’ll be standing before a set of heavy silver doors marked with a red plastic sign that reads, in effect, Metro North emergency exit. On this spot, you’re standing directly over Track 61. Behind those silver doors are stairs that lead down to the fabled secret platform-or, at least, that’s what my track map of Grand Central Terminal shows. And if you happen to see Pershing, Roosevelt, or Warhol emerging from those doors, do please write me.

-E.B.