NEW YORK (CBSNewYork) — In a city known for iconic buildings Grand Central Terminal is a jewel in New York’s crown.

The ornate landmark turns 100-years-old this week.

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For a century, Grand Central Terminal has been the heart and hub of New York City. It’s one of the largest and busiest spaces in New York.

“‘This place is as busy as Grand Central station.’ What other building do we use that same simile for?” said Sam Roberts, author of “Grand Central.”

The station has been featured in films including the classic “North by Northwest” and the original CBS TV Studios — home to Edward R. Murrow and “What’s My Line” 40 years ago — were housed upstairs where the tennis court is now.

“When I first walked into the place I was like, ‘My God,'” said Grand Central Terminal Superintendent Harry Kelly.

By the time he started working at Grand Central, the terminal had fallen on hard times.

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“In the 70s, 80s, the place was a dump, there’s no question about it,” Roberts said. “Homeless were sleeping in what used to be the main waiting room; they were sleeping in the tunnels below the station. There was grime, there was soot.”

The owners wanted to tear it down, just like the original Penn Station, but Grand Central had a powerful champion, Jacqueline Kennedy Onassis.

“Jackie O was instrumental to saving Grand Central,” Roberts said.

After years of neglect, the terminal was restored to its original grandeur.

“People who come here, work here, who earn their livings here, who pass through here and they’re what this palace is all about. And when you stand on the balcony over the concourse it appears like an urban ballet,” Roberts said.

Today, Grand Central terminal is one of the top 10 most visited attractions in the world with more than 20 million visitors each year.

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