1

National Mall’s hidden tunnel (Washington, DC)

The National Mall landscape in Washington, DC, is so familiar that it’s hard to imagine anything hidden beneath it, but there is more going on below the surface than most visitors realize.

Beneath parts of the Mall, a network of underground tunnels connects buildings like the Smithsonian Institution Building, a.k.a "The Castle", with other Smithsonian facilities, including the National Museum of Natural History. They’re mainly used for utilities, secure staff access, and behind-the-scenes operations that keep the museums running smoothly.

2

Mount Rushmore’s secret chamber (Keystone, SD)

When you look at Mount Rushmore, the first thing you notice is the four faces of George Washington, Thomas Jefferson, Theodore Roosevelt, and Abraham Lincoln, but there’s more than meets the eye. Hidden behind Lincoln’s head is a secret chamber known as the "Hall of Records," a place visitors have rarely ever seen. It was the idea of sculptor Gutzon Borglum, who imagined it as a grand room to hold important US documents and tell our story as a country. Construction began with that goal, but the project was never completed. Today, the chamber remains unfinished, but it's there, waiting to be visited someday.

3

The Las Vegas sign is in another city (technically, Paradise, NV)

Do you have the classic picture in front of the iconic "Welcome to Fabulous Las Vegas" sign? If you snapped it and then drove to another city, we hate to break it to you, but you weren’t in Las Vegas.

The famous sign, installed in 1959, actually sits a couple of miles outside the city limits. In fact, the sign and most of the Strip are technically located in the towns of Paradise and Winchester, unincorporated communities in Clark County, Nevada, not within Las Vegas itself. And that’s no accident: much of the Strip and its casinos were originally developed outside the city in the 1950s to avoid municipal taxes and regulations.

4

Fragments of the Antarctic ice sheets (Denver, CO)

Did you know that the Mile High City stores miles of ice from Greenland and Antarctica? Ok, but how?

At Denver’s National Ice Core Laboratory, part of the Federal Science Center, the ice is kept at around -32.8°F. Researchers study it not just to understand Antarctica itself, but also to inspect Earth’s history. Some of these blocks of ice are hundreds of thousands of years old, and from them, scientists can reconstruct ancient temperatures, track greenhouse gas levels, and even identify major volcanic eruptions preserved in the layers.

5

The hatch at the top of City Hall Tower (Philadelphia, PA)

Counting the statue of William Penn at its summit, the tower of Philadelphia City Hall rises about 548 feet, making it the tallest municipal building in the United States. But hidden high above the street, the statue conceals a little-known secret.

At its base is a small hatch, originally built to give workers access for maintenance. It offers an incredible vantage point over the city, but getting there isn’t easy. To reach it, you have to climb narrow stairways and walk through tight, elevated passageways. Would you dare give it a try?

6

A 112,544 square-foot underground bunker (White Sulphur Springs, WV)

The tense atmosphere and threats of the Cold War led to the construction of thousands of underground bunkers across the US. And one of the most impressive is right beneath the Greenbrier Resort in White Sulphur Springs, West Virginia.

Buried 720 feet into the hillside, this 112,544-square-foot bunker was created to shelter all 535 members of the US Congress in the event of a nuclear attack. Built between 1958 and 1961, it was sealed behind a 25-ton blast door, and it remained a protected secret for more than 30 years.

7

Catacombs underneath City Market (Indianapolis, IN)

In downtown Indianapolis, the City Market has been a gathering place since 1886, filled with local vendors, cafés, and shops. But there’s more to it than what you see above ground. Beneath the market lies a network known as the City Market’s "catacombs."

Despite the name, the reality isn't quite so macabre; they’re a series of brick archways that once supported Tomlinson Hall, a huge market building demolished in the mid-20th century. Today, this underground space remains as a hidden piece of the city’s past, but unlike many places on this list, it’s occasionally open for guided tours.

8

One of history's biggest art heists (Boston, MA)

We all know Boston as the "birthplace of the American Revolution," home to events like the Boston Massacre and the Boston Tea Party. But there’s another chapter of its history you don’t hear about as often.

Just over 30 years ago, Boston was the scene of one of the biggest art heists in history. In the early hours of March 18, 1990, two men disguised as police officers entered the Isabella Stewart Gardner Museum, overpowered the guards, and stole 13 invaluable works of art, including pieces by Vermeer, Degas, Rembrandt, and Manet. To this day, the case remains unsolved, and a multi-million-dollar reward is still offered for information.

9

One of the quietest places on Earth (Minneapolis, MN)

Where do you think the quietest places on Earth are? You might imagine remote landscapes far from civilization, but one of them is actually right in Minneapolis, Minnesota.

Inside Orfield Laboratories, there’s a room with no windows or natural light, an anechoic chamber that absorbs nearly all sound. That’s right: it blocks almost every noise, making the space even quieter than a vacuum. Visitors say the silence is so intense that you can hear your own heartbeat and even the faintest movements of your body. Simply incredible.

10

A strange law (Los Angeles, CA)

Why would a city actually pass an ordinance saying that licking toads is a bad idea? That’s Los Angeles, a place full of quirks, some charming, some downright strange. Even its laws can be unusual.

The Colorado River toad, found in parts of California, secretes chemicals that can have powerful psychoactive effects on humans. Because of the risks, both possession and use of this substance are illegal statewide. In 1994, cases occurred, including a teacher who was arrested for possessing the toad substance. But Los Angeles went a step further, passing an ordinance that specifically bans licking these amphibians. And let’s be honest, the poor toad probably doesn’t enjoy it either.

1

It was almost completely torn down

Did you know that very little of today’s White House interior is actually original? Looking at the building now, it’s hard to imagine that it was once so unstable that it was in danger of collapsing.

By 1948, after decades of heavy use, outdated wiring, poor structural supports, and years of renovations layered over one another, the White House had become unsafe. Floors and walls cracked, and parts of the residence were literally sinking. President Harry S. Truman even joked that the place felt haunted because it made so many strange noises. Rather than abandon it, Truman launched a massive reconstruction project with Congress. Between 1948 and 1952, nearly the entire interior was gutted and rebuilt while the original exterior walls were preserved, giving America a strong and reliable White House.

2

During WWII, they built an underground bunker

Did you know there’s a fortified bunker hidden beneath the White House? A couple of years before Truman’s famous renovation, another major project was quietly built beneath the presidential residence.

In 1942, during World War II, President Franklin D. Roosevelt ordered the construction of a secure underground shelter to protect government leaders in case Washington, D.C., came under attack. Built quickly and in great secrecy, the bunker was completed within months, though it was luckily never needed during the war. Today, the facility is known as the Presidential Emergency Operations Center, or PEOC, and it was famously used in 2001 by President George W. Bush and again in 2020 by Donald Trump.

3

It was not originally meant to be white

Can you imagine if it were called "the Gray House"? Today, it’s impossible to picture America’s most famous home as anything other than bright white, but that wasn’t the original idea.

During construction in the 1790s, workers covered the exterior sandstone with a lime-based whitewash to protect it from moisture, cracking, and harsh winter weather. The coating gave the building a pale grayish appearance, not the brilliant white we recognize today. A long-standing myth claims the White House was painted white to hide the burn marks left after British troops set it on fire in 1814, but in reality, the building had already been whitewashed years earlier. Still, after the fire and reconstruction, the white exterior became permanent and eventually inspired the famous name "White House," though for many years people still called it the "President’s House."

4

10 people have died in the White House

Many people have lived and worked in the White House over the centuries, but, according to the White House Historical Association, only 10 people are officially recorded as having died inside the presidential residence.

Among them were two U.S. presidents. William Henry Harrison died there at age 68 in 1841 after falling seriously ill, likely from contaminated water. Zachary Taylor died at age 65 in 1850 from a severe stomach illness after attending Fourth of July celebrations in extreme heat. Three First Ladies also passed away in the White House: Letitia Tyler in 1842, Caroline Harrison in 1892, and Ellen Axson Wilson in 1914. Other deaths included presidential relatives, aides, and staff members, among them Abraham Lincoln’s son, Willie Lincoln, whose death at the age of 11 in 1862 deeply affected the family and became one of the White House’s most heartbreaking stories.

5

Presidential whims

Not every White House renovation happened due to war, damage, or urgent repairs. Some changes came simply from the personal tastes and hobbies of the presidents who lived there, and over the years, there have been quite a few memorable ones.

In 1973, Richard Nixon installed a one-lane bowling alley beneath the North Portico. Years later, in 1989, George H. W. Bush added a regulation horseshoe pit near the White House grounds, where he often relaxed and challenged visitors, including Queen Elizabeth II, to games. Then, in 2009, Barack Obama had the South Lawn tennis court modified so it could also be used for basketball, one of his favorite sports.

6

Jackie Kennedy's furniture

When the Kennedy family entered the White House in 1961, the first lady was disappointed to find that many of the historic rooms had lost much of their original character.

Determined to restore the White House’s history and elegance, Jackie Kennedy famously launched a massive restoration effort. She helped create the White House Fine Arts Committee, brought in historians and curators, and filled the residence with genuine antiques and historical pieces tied to past presidencies. On February 14, 1962, an estimated 46 to 56 million people tuned in to watch the First Lady’s televised tour of the White House, making it one of the most-watched programs of its era. She also supported a congressional act that made many of the White House’s historic furnishings official property of the nation, so future presidents could no longer sell, replace, or discard them.

7

Official name changes

As we mentioned, the building was not always white, and therefore was not always officially called the White House. For much of the 19th century, Americans usually referred to it as the "Executive Mansion" or the "President’s House." Even after its famous white exterior made the nickname popular, it still was not the building’s official name.

That finally changed in 1901, when Theodore Roosevelt began printing "The White House" on presidential stationery. According to official sources, Teddy Roosevelt preferred this name because it clearly separated the president’s residence from the many state "executive mansions" used by governors across the country.

8

It was once America's largest house

There is one thing about the White House that no one can deny: it has always been huge, even in its early days.

When the White House was first occupied in 1800, it already contained more than 100 rooms spread across three floors, making it one of the grandest homes in the United States at the time. In a time when most Americans lived in modest houses or farms, the presidential residence was seen as a palace. Many historians even consider it the largest private residence in the country during its early years. Today, the White House covers about 55,000 square feet, though modern private buildings, like the Biltmore Estate in North Carolina, are now far larger.

9

President Benjamin Harrison’s fear

Among the many changes the White House has undergone over the years, few were as revolutionary as the arrival of electricity.

For nearly a century after it was built, the presidential residence relied on candles, oil lamps, and gas lighting. That finally changed in 1891, when electricity was installed during the presidency of Benjamin Harrison. But, like many families in that era, the Harrisons were not exactly thrilled by this modern invention. According to White House stories passed down over the years, President Harrison and First Lady Caroline Harrison were so nervous about the possibility of electric shock that they rarely touched the light switches themselves. Instead, they often asked the house staff to turn the lights on and off for them.

10

Hillary Clinton’s special gift

Of course, Jackie Kennedy wasn’t the only First Lady to leave her mark on the White House. Hillary Clinton added her own personal touch as well, this time as a gift for her husband.

In 1996, Hillary Clinton transformed a little-used room on the White House’s third floor into a private music room for President Bill Clinton. The gift came during the year of Bill Clinton’s 50th birthday and reflected one of his best-known passions: music. Complete with space for listening to records and playing his famous saxophone, the room gave the president a quiet retreat inside the White House.

1

House Size

Image: Esther Zheng

One of the very first things any prospective homeowner should ask themselves is what kind of house they want . Having a general idea of the size, as well as the amount and type of spaces needed, is considered basic information before starting to look for a property.

2

Roof Condition

Image: Andreas Weiland

For practical reasons, most people looking to buy a house don’t inspect the roof of a prospective home. However, that section of the house can present serious and costly problems if it has any kind of damage.

Asking about the condition of the roof is paramount. How old is it? What is it made of? Buyers can find this information on the seller’s disclosure or ask the real estate agent to find out. Asphalt shingle roofs last around 20 years, but other materials, like clay or metal, can last much longer.

3

Neighborhood Safety

Image: Alev Takil

It goes without saying: safety is a big thing. When searching for a home, make sure the neighborhood where a potential house is located is safe. It’s also highly advisable to check out the neighborhood from an insider’s perspective via social media, such as Facebook groups, where you can learn more about the area and ask locals questions.

If you’re truly interested in a particular home, spend some time in the neighborhood. Go for a walk and check out local businesses to get a feel for what it’s like to live in the area.

4

HVAC system

Image: Taylor Vick

The HVAC system heats and cools a house year-round. Anyone looking at houses should ask about the type of heating and cooling system each one has and, most importantly, how old it is. Asking for maintenance records is also a good idea.

Furnaces and AC units typically last anywhere from 10 to 25 years. If a unit is broken, repair costs vary based on the type of system and how big it is. Homeowners can spend an average of $7,000 to replace an existing HVAC unit—but don’t count on a home warranty to automatically cover that.

5

Property Taxes

Image: Recha Oktaviani

A commonly overlooked item for first-time homeowners when searching for a house is property taxes. When considering a potential home, always compare property tax amounts over several years to help you calculate the overall affordability of the property .

To find out a home's estimated property taxes, check with the county's appraisal board. Homeowners Association dues should be listed in the home's listing, or you can request them from the listing agent.

6

Plumbing

Image: PAN XIAOZHEN

The plumbing system in a house can be a mystery for a prospective buyer if they don't know how to inspect it properly. Pipe disintegration, obstructive tree root growth, and complicated clogs can all cause havoc on the system. Keep in mind that sewer line replacement can cost anywhere from $1,300 to $4,900.

Always check toilets for leaks, unstable bases, and discoloration . Look under the bathroom and kitchen sinks for signs of leaks. Turn on the hot water in the sink or tub to see if it gets hot. If it doesn’t, that could indicate a problem with the water heater.

7

Water damage and mold

Image: Hydra 4x

Water damage can cause numerous problems in a house, including structural issues, mold, and rot, especially in basements. Anyone inspecting a house should pay close attention to musty smells as well as water stains on floors, walls, or ceilings .

The cost of mold removal can be anywhere from a few hundred to a few thousand dollars, depending on the size of the affected area. And, because mold is a health hazard, it should be treated before moving in.

8

Proper ventilation

Image: Jelleke Vanooteghem

This one might be subtle, but it’s very important, especially when considering the mold issues mentioned earlier. Without adequate interior ventilation, moisture can't evaporate , which can turn a room into a breeding ground for mold.

Look for condensation on windows or slightly bubbled or peeling paint around windows, doors, or vents. These signs may indicate moisture within the walls or ceiling drywall.

9

Noise Level

Image: Rei Kim

Nobody wants to live in a noisy home. But, at the same time, this issue is often overlooked when searching for houses. Many showings are cunningly scheduled during quiet hours to disguise the noise issues.

If you are truly interested in a property, visit during high-traffic hours to assess this concern . Even if the house is perfect in every other way, the constant hum of passing cars, public transport, or other sources of noise can become a serious problem.

10

Foundation and home exteriors

Image: Aiden Craver

Foundations matter. Bulging or bowing foundation walls are signs of structural weakness that can be expensive to repair. Always check for cracks in the foundation, drywall, or ceiling ; gaps above doors and windows ; sunken stairs or porches; and sloping or uneven floors or tiling.

Of course, not every crack means the home is about to collapse. Every home experiences some degree of settling, so some cracks are to be expected.

11

Electricity issues

Image: Mila Albrecht

The electrical system in a house can be compared to the nervous system of a human being: every part must work properly, and issues can sometimes be difficult to spot. From the power outlet next to the bed to other electrical systems in the house, like the garage door opener, everything is important and contributes to your safety and comfort. Bring a phone charger and plug it into random sockets to check if they work properly .

12

Room for improvement

Image: Daniel McCullough

Buying a house is a big investment and you can be living in it for a very long time. Therefore, it is always important to take into consideration any future plans and whether these plans make sense in that particular house.

Is there a wall you could knock out to create more space if needed? A garage or attic you could potentially finish if you need an extra room? Having an easy-to-modify layout can provide more possibilities for the future.