Sandwiched between its iconic four-sided clock and the newly opened Apple store, New Yorkers with dynastic surnames like Kennedy, Vanderbilt, and Bloomberg gathered in Grand Central Terminal (GCT) Friday to celebrate the historic building’s 100th birthday. Designed by Reed & Stern, in association with Warren and Wetmore, the terminal opened its doors in February 1913, quickly becoming an emblem of a particularly prosperous time in New York. Fittingly, the Grand Central Centennial Committee staged the day-long 100th birthday event in a small roped-off area in the middle of the soaring main concourse, allowing the din of rushing commuters to accompany the ceremony.

Citing the 750,000 passengers that move through the terminal each day and the torrent of real estate pressures that have threatened it in the past, New York City Mayor Michael Bloomberg quipped, “it’s not easy to last a hundred years in a city of change,” concluding that GCT is “the best looking centenarian around.”

Not only is the fact of its age an impressive enough marker, the 100-year milestone was made all the more poignant because it very nearly didn’t happen. Through the 1960s and '70s, the terminal was embroiled in a pitched battle over whether to raze or preserve the Beaux Arts structure, a fight that would ultimately reach the U.S. Supreme Court in 1978. Were it not for the 1963 destruction of nearby Pennsylvania Station, which energized the historic preservation movement, GCT may very well have been dispatched in the same way.

Friday’s celebration, then, was as much a birthday party as it was a victory lap for preservationists, which was evidenced by list of speakers that included Robert Tierney, chair of NYC Landmarks Preservation Commission, and Rose Harvey, commissioner of the New York State Office of Parks, Recreation, and Historic Preservation. Neglected for decades during the mid-20th century, GCT had deteriorated from its Gilded Ageglory. “The terminal was in great disrepair; it was broken in every sense of the word,” remembered Centennial Committee chair Peter Stangl. “The first impression that a lot of people had of New York City was rather dismal,” Stangl added, referring both to the regional travelers arriving by train and the swaths of tourists who visit the terminal early in the NYC itinerary.

Caroline Kennedy—whose mother, Jacqueline Kennedy Onassis, championed the GCT’s preservationist cause—participated in Friday’s celebration as the honorary chair of the GCT Centennial Committee. She read from a letter that Onassis had sent to then-New York City Mayor Abe Beam, urging him to save GCT, “so that we won’t all end up in a uniform world of steel-and-glass boxes.” Citing her mother’s unyielding determination, Kennedy joked that “Mayor Bloomberg is probably happy she’s not around.”

And for those who missed the festivities, a new exhibition organized by the New York Transit Museum, “Grand by Design,” is installed in GCT’s Vanderbilt Hall through March 15, and documents the architectural and engineering history of the terminal. This is accompanied by the new book Grand Central Terminal: 100 Years of a New York Landmark. Thoughtfully researched, the two presentations provide a robust survey of important historical markers.

While the roster of speakers at the official celebration lavished attention on the many architectural marvels of the original building—and on the results of its later preservation—Bloomberg, a results-oriented mayor, underscored its enduring functionality as a particularly impressive measure of success. “This is a commuter train station,” he reminded the audience. This was a theme picked up by New York Gov. Andrew Cuomo’s deputy secretary for transportation, Karen Rae. “For all the beauty of the building,” she said, “it is remarkable for what it truly is: a transportation hub.”