We start our list with a moderately well-known fact: the Statue of Liberty’s beautiful emerald color is not original. Technically, it’s a sign of damage. While the statue's infrastructure is made of iron, its exterior is copper, which has turned green over time due to oxidation.

Fortunately, that same green coating now protects the statue from further damage and deterioration.

Image: Pierre Blaché

A busy train station may not seem like the ideal place for a social club, but that’s exactly the case with the Explorers Club. Operating for decades, this exclusive venue primarily serves locals, featuring a full gym, an indoor hard court, and even a smaller secondary court.

Image: David Vives

This beloved St. Louis landmark holds a secret at its peak: a time capsule was placed inside the arch in 1965, containing 762,000 signatures—many from students who attended St. Louis schools at the time.

The capsule is permanently welded inside the arch and will remain sealed for as long as the structure stands.

Image: Chris Hardy

New Yorkers seem to have a penchant for sports courts hidden on the top floors of iconic buildings—this one being the second on our list. The New York High Court Building is primarily a place for legal proceedings and bureaucratic work, but on its fifth floor, visitors will find a basketball court known as the "Highest Court in the Land."

Image: Markus Spiske

It’s easy to imagine hallways and rooms filled with endless state secrets in the White House basement. But what most people won’t guess is that you can also find a dentist’s office, a carpenter’s shop, and even a bowling alley down there.

Image: Benyamin Bohlouli

As strange as it sounds, this statement is true in a sense. The complex system of pumps and gates that administer the water of the Falls can be controlled by a central command.

In fact, part of Niagara Falls is even scheduled to be "turned off" in the coming years to replace some obsolete structures—just like a faucet.

Image: Tosab Photography

Graffiti has been around all over the world, for a couple of centuries now. The Washington Monument was still under construction when the Civil War broke out, and Union soldiers stationed there carved their names and drew pictures onto the monument. These markings can still be seen today at its base.

Image: Sonder Quest

One of America’s most famous landmarks hides a secret room known as the Hall of Records, which is filled with documents intended to preserve the nation’s history for future generations. This hidden chamber is accessed through a concealed door behind Abraham Lincoln’s ear.

Image: Jéan Béller

Speaking of Lincoln, you’ll need a flashlight to spot this one—but it’s there. On the north wall stone of the Lincoln Memorial, the letters "EBL" can be seen carved. These initials stand for Evelyn Beatrice Longman, the artist who sculpted the memorial’s ornamental border.

Image: Andy Feliciotti

As it turns out, the Empire State Building has one more floor than the famous 102. This extra floor was originally constructed for building maintenance but now serves as an exclusive hotspot for celebrities, complete with an ultra-thin, knee-high railing separating observers from the sky surrounding them.

Image: Kit Suman

Wine cellars are cold and dark places—just like the basements at the Brooklyn Bridge’s bases. This connection, now quite obvious, was made by the bridge’s engineer, Washington Roebling, who incorporated two full wine cellars into the bridge’s bases on each side and then rented the space to local businesses who needed the extra storage.

Image: Partha Narasimhan

If a trip to Disneyland isn’t enough of a Disney experience for you, there’s an exclusive club on the premises called Club 33. This exclusive joint boasts an invite-only guest list, where members must pay anywhere from $25,000 to $100,000 to join, with annual membership dues ranging from $12,500 to $30,000. Do you think it’s worth it?

Image: Travis Gergen