NEW YORK (CBSNewYork) -- The Westminster chimes of the great two-ton clock in the center lobby are counting down the hours until the Waldorf-Astoria closes its doors for a two to three year update.
As CBS2's Scott Rapoport reported, she was the Grand Dame of her day, a landmark architectural jewel and cultural touchstone of New York City.
"It's very special. It's iconic. We'll never see a place like this again," said Doug Wellenbacher, who has worked as a doorman there for 24 years.
Throughout its storied 86-year history, its hallowed halls hosted some remarkable happenings -- from Old Blue Eyes, Frank Sinatra with band leader Guy Lombardo in 1949, to former Gov. Nelson Rockefeller joking with Russian leader Nikita Khrushchev in 1959, to Hollywood stars Tony Curtis and Janet Leigh in the honeymoon suite in 1951, and Eunice Kennedy Shriver dancing at her wedding with her father, patriarch Joe Kennedy.
Since Herbert Hoover, the Waldorf-Astoria hosted every president, including John F. Kennedy, as well as luminaries such as Grace Kelly, Marilyn Monroe and Queen Elizabeth.
"The cultural and social and economic elite for years and years," said Daniel Geiger, a real estate reporter for Crain's.
The historic hotel was also home to a number of secrets, including a tunnel and train track deep underground, Rapoport reported.
Track 61 was secretly used to transport former President Franklin Delano Roosevelt and his vehicle from Grand Central Terminal to the hotel during his trips to New York without anyone seeing him. Roosevelt had polio and historians say he insisted on keeping his illness private.
"His car apparently is still down there," Geiger said.
With the Waldorf-Astoria officially closing at checkout time Wednesday, the last guests marked the moment with more than a touch of melancholy.
"I just think it's tragic. Really it is," said Marilyn Diliginti, of Vancouver.
"I thought they would be open forever." another woman said.
One man strolled into the hotel for the final time, wearing a tuxedo for a work event, 1010 WINS' Al Jones reported.
"(There are) so many new buildings going up in New York City, so it's always good to kind of look back a little bit, instead of always looking forward," he said.
Another said this is where his grandfather celebrated those special moments.
"He took me for my first dinner after Communion here. So there are memories and sentimental embellishments that will never leave me," he said.
Jones also spoke with a man who was enjoying one last cocktail in the piano lounge.
"One of the last great, classic hotels. You know, one by one they're disappearing," he said.
A number of the rooms are to be transformed into condos, and the vintage 1931 hotel will get a freshening up, WCBS 880's Rich Lamb reported.
The landmark will convert 1,100 hotel rooms into condos, leaving only 300 to 500 for hotel guests, the Wall Street Journal reported in June 2016.
The Waldorf's historic facade and famed grand ballroom, will also be kept as is.
Anbang Insurance Group, a Chinese insurance company, bought the hotel from the Hilton Corporation for $1.95 billion in 2014. Hilton will continue to manage the storied hotel for the next 100 years as part of an agreement with Anbang.
After the sale, the State Department and the White House checked the out of the hotel. There was no formal announcement made, but analysts said it likely had to do with Chinese spying.
The Park Avenue hotel has restaurants including Peacock Alley, Bull and Bear Prime Steakhouse and Oscar's.
Millionaire William Waldorf Astor opened the first Waldorf Hotel at Fifth Avenue and 33rd Street in 1893. The Astoria Hotel was constructed on an adjacent site in 1897, according to the hotel's website.
The first Waldorf-Astoria closed in 1929 and was torn down to make way for the Empire State Building.
The current hotel was completed in October 1931 at 301 Park Ave. between 49th and 50th streets. It was the tallest hotel in the world at the time at 625 feet.
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