Can a color be a worldwide celebrity? It seems so! This is the case of the famous "international orange" of the Golden Gate Bridge in San Francisco, California.

It's hard to imagine this iconic bridge in any other color. But believe it or not, it was once about to be painted in another hue.

The original idea was to paint the Golden Gate Bridge black with yellow stripes to make it visible to ships and planes. However, the sharp vision of consulting architect Irving Morrow changed the plans. When he saw the reddish color of the primer used on the iron, he realized that this color would work much better and would also give the imposing structure an original touch.

Image: Alexey Komissarov

We all know that incredible creatures and breathtaking landscapes await us in Yellowstone. You probably also know that this amazing area that covers more than 3,400 square miles in parts of Wyoming, Montana, and Idaho was the first national park in the United States. Not only that, it was actually the first national park in the entire world!

But, while it's totally famous and celebrated today, there was a time when only a few knew about this place. Early explorers who walked Yellowstone in the 19th century wrote detailed journals about what they saw and experienced there, but when they returned, they found that people didn't believe their stories. We have to admit that those skeptics had a point; such a beautiful place seems out of this world!

Image: Hana Oliver

Nobody can deny the metro system is great. Its speed and efficiency allow thousands of people around the world to get to their homes and jobs every day. Did you know that the members of the U.S. Congress have their own subway system right underneath the Capitol building?

That's right! Under the impressive structure that houses U.S. Representatives and Senators lies an entire subway system. This allows workers there to access different parts of the complex in a matter of seconds. It must make things easier on busy days, don't you think?

Image: Louis Velazquez

But not all of the Capitol's surprises are underground; some are in plain sight. We're talking about the spectacular dome that crowns the famous neoclassical building in Washington, D.C. While the dome is a symbol of our country today, there was a time when the Capitol Building didn't have this gracious final detail.

The construction was considered completed in 1800. However, one last touch was still needed. In 1824, the first and smaller dome arrived, made of wood. Finally, it was replaced in 1866 by the impressive dome we see today, which stands an incredible 288 feet high and is made of cast iron, brick, stone, and copper.

Image: MIKE STOLL

The Liberty Bell must be one of the most recognized icons of the United States. Preserved as a symbol of our Independence, everyone can visit the famous bell at the Independence Hall in Philadelphia, Pennsylvania.

In addition to its well-known history and its famous "crack," this bell has even more hidden details to discover. When you read the inscription on the Liberty Bell, you'll be able to read "Pensylvania" instead of "Pennsylvania." While you could think that those in charge of inscribing the bell weren't paying attention, it wasn't actually a misspelling; it was one of the accepted spellings for Pennsylvania in those days.

Image: Dan Mall

Whether in person or through the screen, we all had the chance to see the legendary Hollywood sign over Mount Lee in Los Angeles, California.

But, while this landmark is recognized around the world today, it didn't always look as we see it now. The Hollywood sign had several changes throughout its history. It was first erected in 1923 as an advertisement for a real estate development. At the time, it read "Hollywoodland" and even had lights, illuminating the entire area at night.

Many things happened in our country before 1949, when the last four letters were removed, leaving just the current "Hollywood."

Image: Justin Aikin

As we grow older, we understand one truth: good things often take time. While patience seems to be in short supply these days, it was certainly in abundance for those who built the impressive Mount Rushmore National Memorial, one of our most famous attractions.

The construction of this imposing monument that features the faces of George Washington, Thomas Jefferson, Theodore Roosevelt, and Abraham Lincoln began in 1927 and took 14 years to complete. Carving four 60-foot-tall heads on a granite hill is no easy task. But, on top of that, some budget difficulties slowed down the process even more.

Image: Jeromey Balderrama

Mount Rushmore National Memorial has more secrets to disclose! Although not visible to the naked eye, there is a particular detail among the heads of Washington, Jefferson, Roosevelt, and Lincoln. Want to know what it is?

If you haven't heard about it, this might surprise you: there is a small door right there on Mount Rushmore. Mysteries everywhere! The door leads to a chamber known as the "Hall of Records." According to the plans of sculptor Gutzon Borglum, this spot would hold important documents and objects of our history.

Image: John Bakator

Besides being the tallest human-made monument in the United States and also the tallest arch in the world, the famous Gateway Arch in St Louis has much more to offer.

During its construction in the 1960s, a curious detail was placed inside its iconic metal structure. At the base of the monument, you can find nothing less than a time capsule!

The capsule, which contains various artifacts and relics from our country's history and culture, was thought to give future generations an idea of what the world and the United States were like in those days.

Image: Mark Serafino

At 555 feet tall, the Washington Monument is one of the most imposing in our country. But besides its height, this landmark also possesses a couple of surprising facts.

It might seem that graffiti is a modern artistic expression that has only been around recently, but this isn't the case, and the Washington Monument is proof of that. At the structure's base, there is a series of graffiti made in the 19th century, during the Civil War.

That's right! Many people and soldiers passing by at the time left signatures, dates, and patriotic messages inscribed on the famous obelisk, and some of them are still visible!

Image: Dineda Nyepan