(Photo: Underwood & Underwood/Corbis)

John D. Rockefeller Jr.’s subterranean escape route out of 740 Park Avenue to the railroad tracks underneath the street (where his private train could pull up) has long been “a wonderful urban myth,” says Michael Gross, author of 740 Park: The Story of the World’s Richest Apartment Building. Gross didn’t mention it in his book after the Rockefeller relatives denied it. But not everybody’s so sure. Stephen Del Savio, a subsurface plumber and vice-president of NYC Water Works, was working with his crew about fifteen feet under Park last summer and discovered a sealed-up vault. Upon entry, just outside 740, they found a series of brick chambers about ten feet tall, six feet wide, all with arched ceilings, branching off from 740’s basement. “I was, like, ‘Holy shit!’ ” he says. “This thing was certainly leading somewhere.” Was it an old wine cellar? Remnants of a building built before 740?

Checking pipes under the city’s streets, Del Savio has stumbled upon an abandoned pool (under Brooklyn’s St. George Hotel) and a barber shop (under the Hotel Pennsylvania), but nothing so tied to city royalty. Rockefeller once owned 740 Park, home to Bouviers, Bronfmans, Guggenheims, and J. Watson Webb, a member of the Vanderbilt clan—the family that built the New York Central Railroad. So whodugit? “My money is on the Vanderbilts,” says Columbia historian Kenneth T. Jackson.

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Related:

• Archive: “Intelligencer”
• Articles by Geoffrey Gray
• Table of Contents: Jan 15, 2007 issue of New York | Subscribe!