New York City’s Grand Central Terminal (GCT), the second most visited tourist spot after Times Square, is the largest railway terminal in the world with 49 acres, 44 platforms, and 33 miles of track. It used to be called Grand Central Depot, later Grand Central Station, and now it is called Grand Central Terminal because trains originate and terminate at this spot. The tracks below are a giant loop so the trains never need to be turned around. When passengers get off at GCT, the train is already turned around facing the opposite direction, which explains why it seems to take forever when you’re on a train and enter the tunnel below the Terminal.

The beaux-arts style building is one of the country’s greatest architectural achievements, ranking Number 13 on the American Institute of Architecture’s list of America’s Favorite Architecture.

Each day during morning rush hour, trains stop on the platform tracks every 58 seconds and 1,200 customers get on or off. Every day, a total of one half a million people pass through Grand Central Terminal, though that number doubles during the holiday season. Grand Central Terminal is the second busiest train terminal in North America after Penn Station, also in NYC. However, new tracks are being built beneath GCT and soon passengers will be able to take any Penn Station train to and from Grand Central.

On the main floor is an information booth, above which is a four-sided clock made from precious opal and estimated to be worth $10 to 20 million. On top of the clock is an acorn. Cornelius Vanderbilt, the original builder and America’s first tycoon, came from humble beginnings, with no symbol or coat of Arms, so he chose the acorn as his family crest. “From small acorns come mighty oaks,” he said. Acorns are everywhere at Grand Central Terminal, even hidden in the latticework leading to the tracks.

Inside the information booth is a secret spiral staircase leading to the lower level so the information booth attendants don’t have to cross the main hall to go downstairs. Each hour, the attendants are asked more than 1,000 questions. Clocks are important at GCT. A train is intentionally listed to leave a minute sooner than its actual departure time so that someone racing for the train won’t be left behind. Outside the building is another clock, the largest Tiffany clock in the world.

‘There is another clock on an archway in the main concourse that reads “Eastern Standard Time.” At one time in America nothing was standardized when it came to time. One town’s time might be 4:00pm while in another town, the time was 4:10. To prevent this, the United States divided the country into four main time zones (Eastern Standard Time, Central Standard Time, Mountain Standard Time, and Pacific Standard Time. Eastern Standard Time originated from this clock at Grand Central Terminal (which does not change by an hour during Daylight Savings Time).

When you look up at the massive domed ceiling, you see a constellation of the Mediterranean night sky. Originally, Vanderbilt wanted a glass ceiling, but when told the cost, he decided on a painted ceiling instead. Because he was an amateur astronomer, he commissioned the Zodiac. Unfortunately, the muralist mistakenly painted it backwards. Vanderbilt was unwilling to pay to repaint the ceiling. Instead, he told everyone that it was from “God’s vantage point.

In 1957, Sputnik, the first artificial Earth satellite, was launched into space by the Soviet Space Program. Not wanting to be undone, NASA decided to display a Redstone rocket in the great dome, but the rocket was six inches too tall, so they drilled a hole, still visible on the ceiling. It is right next to Pisces, the fish.

If you look up to one corner of the famous ceiling, you will see another more recent, secret which is thanks to Jackie Onassis. After the U.S. Supreme Court ruled to preserve the building’s historic landmark status, former First Lady Jacqueline Kennedy Onassis helped save the building (the renovated main entry foyer on 42nd Street and Park Avenue is named for her). Follow one of the ceiling’s “crab” claws to the end and there is a tiny black brick which shows the color the ceiling used to be – not from pollution but from nicotine. In those days, everyone smoked. The patch was left as a reminder to show how much work had been done.

One more detail about the main concourse: the East Staircase was created during the 1996 renovation, a mirror image of the West Staircase except the newer steps are exactly one inch smaller than their counterpart. On the lower level is a food court and the famous Oyster Bar.

In front of the entrance to the Oyster Bar is the "Whispering Gallery." Here, two people can stand beneath the large domed ceiling in opposite corners, whisper, and can hear each other perfectly. The romantic corner inspires one marriage proposal each day.

On an even lower level beneath the Waldorf-Astoria is a special station and train car built for President Franklin D. Roosevelt for protection and security. A private elevator brought him and his limousine (from the train) directly up and into his hotel room so he could hide his disability.

There is also a Metro-North Lost & Found Room, in which every item is tagged, and riders can check online to see if their lost item has been turned in. They have a 54% return rate including a prosthetic leg and an urn. They were able to contact the owner of the urn who admitted it contained her husband’s ashes. “Don’t you want it back?” they asked.

“No,” she said. “He was cheating on me, and he took the train to get to her place, so I left him there on the train.”

Grand Central has its own police department and Grand Central Market on the main level with every product made by local vendors. On the main concourse level are shops selling everything from clothes to perfumes. One shop, Central Cellars used to be a movie theatre which showed 5-minute newsreels. Above racks of wine, you can still see the space for the projector. In addition, CBS used to do the news from Grand Central.

There is a private entrance to a space, formerly the private salon and office of 1920s railroad tycoon Joseph Campbell. It was complete with ceilings imported from Italy. a fireplace which contained giant safe, and a Persian carpet worth $3.8 million. Today, it is open to the public and called The Campbell Bar, an ideal spot for a drink.

Grand Central Terminal also has tennis and racquet ball courts. In Vanderbilt Hall there is a City Winery. In addition, up the staircases are respectively, Cipriani’s Restaurant, and an Apple Store. Also on the main concourse is the N.Y. Transit Museum for browsing the history and with products for sale.

Chances are, you won’t be able to find half of the places I’ve just mentioned, so the best way to see GCT is with Take Walks by City Experiences, the new operator of the Official Grand Central Terminal Tour. The VIP tours provide guests with an official tour of this historic landmark, offering a unique perspective of one of the most recognizable train terminals in the world. That’s how I saw it, with a group of both New Yorkers and visitors, including an 11-year-old boy who never got bored. Our guide was Rhiannon Ross, an actress who has been conducting tours for seven years. She was spirited and not only knew the complete history but had an iPad full of historical photos to show us. The tour takes place seven days a week starting at 3pm and lasting for 1.5 hours. Admission is $35.00 for adults and $30.00 for children. For more information: Take Walks by City Experiences.