1

Coca-Cola vs. Pepsi

The "Cola Wars" have been going on for decades, but it seems that there’s no resolution in sight. In the late 1970s, both companies started directing their marketing campaigns against each other, with mixed results , though Coca-Cola always seems to be half a step ahead of Pepsi. They have both gained a loyal following, but the war remains as strong as ever.

2

Hamilton vs. Burr

Political rivalries are not uncommon in America, but few include a deadly duel involving a sitting vice president. The animosity between Alexander Hamilton and Aaron Burr intensified after Burr won a Senate seat from Hamilton’s father-in-law, Philip Schuyler. During the presidential election of 1800 and the New York gubernatorial election of 1804, Hamilton actively supported candidates opposing Burr. Deeply angered by Hamilton’s continued opposition and public criticism, Burr challenged him to a duel, and the rest is history.

3

Yankees vs. Red Sox

Sports fans are dedicated, but few rivalries match the intensity of those who support the New York Yankees and the Boston Red Sox. They have been rivals since their first meeting more than 120 years ago, with the Yankees often being perceived as a dominant team, while the Red Sox filled the role of the underdog . Their enmity deepened dramatically in 1920, when Babe Ruth was sold to the Yankees. What followed was an 86-year championship drought for Boston, popularly known as the "Curse of the Bambino," which the Red Sox finally broke in 2004.

4

Miami vs. Tampa

Can a sandwich cause a rift between two cities? It sure can. Cuban sandwiches are a Floridian staple , and their construction is often considered set in stone: ham, roast pork, Swiss cheese, pickles, and mustard on Cuban bread, served pressed. Unless you live in Tampa. There, a strong Italian influence has translated into the addition of Genoa salami to the Cuban sandwich, much to the outrage of their Miami neighbors.

5

Mark Twain vs. USPS

Renowned writer Mark Twain had no qualms about criticizing the things he disliked, and he surely disliked the United States Postal Service . He thought it costly, inefficient, and overregulated, and he made sure to let everyone know in articles, complaint letters, and conversations with influential figures. In a poetic turn of events, the USPS released a Mark Twain commemorative stamp in 2011.

6

Hatfields vs. McCoys

One of the most infamous feuds in American history, the rivalry between the Hatfield and McCoy families shook the West Virginia-Kentucky area for three decades . Starting with the murder of a McCoy who was returning home from war, the hostilities and deaths escalated to a point where the Supreme Court was forced to intervene.

7

Edison vs. Tesla

Many inventors were involved in the so-called "War of the Currents," waged on electric power systems, but Thomas Edison and Nikola Tesla are the most remembered. Edison championed direct current (DC) electrical systems, which operated at relatively low voltages and were suited to short-distance distribution. Tesla, working with George Westinghouse, promoted alternating current (AC), which could be transmitted over long distances more efficiently. Despite Edison’s strong campaign to discredit AC and its proponents, it ultimately became the standard power system.

8

Joan Crawford vs. Bette Davis

Rivalries are everywhere in the film industry, but some become the stuff of legends. Allegedly, the feud between Joan Crawford and Bette Davis was never as intense as portrayed. While the two actresses did clash at times over personality differences, professional competition, and rumored romantic entanglements, much of the rivalry’s enduring reputation was fueled by gossip columns and sensational press coverage. And their respective film studios took advantage of it.

9

Burger King vs. McDonald’s

The fast-food industry has always had McDonald’s as one of its key players, but other companies have given their all to take that position. Burger King is one of McDonald’s oldest challengers , and has repeatedly tried to influence their customer base through a series of aggressive and often tongue-in-cheek marketing campaigns. While other brands, such as Wendy’s or Five Guys, have dipped their toes in the "Burger Wars," McDonald’s and Burger King remain two of the biggest names in the industry.

10

Edgar Allan Poe vs. Rufus Wilmot Griswold

While Poe looms far larger than Griswold in the modern American mind, much of what the public believes about the "Nevermore" poet was influenced by his rival . Their feud began with the publication of a poetry anthology by Griswold, which displeased Poe due to its contents and criticism of his own poetry. The animosity intensified when they both vied for the same editorial position and, reportedly, the affections of the same woman. After Poe’s death, Griswold wrote an obituary and a biography filled with attacks and slander, which contributed to the idea of Poe as a drunkard and a madman.

1

What are bills made of?

Unlike other currencies, dollar bills are not made of paper or plastic. U.S. dollar bills are made from a special fabric blend composed of 75% cotton and 25% linen. This mix makes the bills extremely durable and resistant, and they can be folded about 4000 times before tearing.

2

What bills are valid?

Any U.S. dollar bill that was legally printed is valid, no matter how old, as American currency does not have an expiration date. While some bills might not be accepted by businesses of foreign exchange services due to their condition or if they are a discontinued version of the bill, the bills themselves are still valid, and American banks will accept them, though they might take them out of circulation.

3

American leaders

Five bills have a depiction of an American president. The exceptions are the $10 bill, with Alexander Hamilton on the front, and the $100 bill, with Benjamin Franklin. The $1 bill, depicting George Washington, is extremely symbolic: several elements are repeated 13 times as a nod to the thirteen colonies, and it showcases the Bald Eagle and the Eye of Providence as a sign of God watching over America.

4

A change in size

Did you know that dollar bills used to be so big that they were nicknamed "horse blankets"? Original dollar bills were 7.4 × 3.1 inches. In 1929, the Treasury Department reduced the size of bills to 6.14 × 2.61 inches to reduce production costs and materials. Old bills, though still valid, are worth much more as collector items.

5

Uniformity

Besides their value and design, all dollar bills have the same size (6.14 × 2.61 inches), color, and weight (1 gram) , which sets American currency apart from other countries where bills of different values are differentiated by size, color, or both. Why doesn’t the U.S. implement differences among bills? The cost of adapting vending machines, bank drawers, and ATMs to new bill sizes would cost billions of dollars.

6

Hard to copy

Originally, dollars were not green, but black. As time passed, green ink was favored, as it was cheap and did not fade as much as black. The new color also prevented people from using black-and-white cameras to create counterfeit money. Currently, dollar bills are predominantly green, but newer versions also include extra colors, such as pink, orange, or purple.

7

A $100,000 bill?

Have you ever seen a $500 or 1,000 dollar bill? What about a $100,000? Up until 1945, the U.S. Treasury printed $500, $1,000, $5,000, $10,000, and $100,000 notes , in addition to the values currently in use. These higher-value notes were mainly intended for bank and government use, but were sought by criminals as they made it easier to hide large amounts of money. Even though they were officially discontinued in 1969, these notes are still valid, though rare, and they have a high worth as collector's items.

8

No numbers

Unlike bills, American coins have different sizes and colors related to their value. Originally, gold, silver, and copper were used for coins, but modern coins are made of copper, zinc, or nickel. Besides their size and design, the value of each coin is printed in letters, not in numbers , alongside depictions of American presidents.

9

Liberty for all (the coins)

By law, all American coins must include six specific details : the word ‘Liberty’, the name of our country, the national motto "In God We Trust", the oldest American motto "E Pluribus Unum", the value of the coin, and the year. Each coin also includes a mint mark that shows where it was made: "P" for Philadelphia, "D" for Denver, "S" for San Francisco, and "W" for West Point.

10

A global currency

The American dollar is one of the most powerful currencies in the world, acting as a backbone for international trade and finances. It is estimated that two-thirds of the physical dollars in circulation are outside American territory. Besides the U.S. and its territories, eight sovereign nations have the U.S. dollar as their official currency, with several more accepting it as legal tender.

1

There's an unexplained billion-year gap

Look closely at the canyon walls, and you'll notice something strange: a clean, sharp line where ancient rock simply stops, and a much younger layer begins directly above it.

This geological puzzle is called the "Great Unconformity," and it represents over a billion years of rock layers that are simply absent , as though that stretch of time never happened. In some spots, rock dated 1.8 billion years old sits directly beneath rock that is only 520 million years old. Where did the missing billion years go?

The leading theory involves the violent breakup of an ancient supercontinent, but scientists are still piecing it together.

2

During the Cold War, it hid a nuclear fallout shelter

During the Cuban Missile Crisis in 1962, the U.S. government converted part of the Grand Canyon Caverns into a fallout shelter. This dry cave system, more than 200 feet underground, was stocked with enough food and water to sustain 2,000 people. Naturally, it was never occupied, and the supplies were never used.

The caverns have since been transformed into a tourist attraction, with organized tours winding through the same underground chambers that were once intended as a refuge from nuclear war. You can even book a night's stay there.

3

The Federal Aviation Administration was founded after a crash over the canyon

In 1956, two commercial passenger planes collided in midair over the eastern Grand Canyon, killing all 128 people on board both crafts. Rescue teams struggled to reach the wreckage deep inside the canyon, and the extreme heat of the crash had caused the planes' aluminum to fuse with the bedrock. There were no survivors.

The disaster exposed a terrifying truth: the U.S. air traffic control system was dangerously outdated, relying on pilots' visual estimates and rough guesswork from controllers , with no way to separate fast-moving aircraft from slow ones, or instrument-flying planes from those navigating by sight. Congress responded by passing legislation that created both the Federal Aviation Administration (FAA) and the National Transportation Safety Board.

4

A hoax suggested that an Egyptian civilization had lived there

In 1909, the Arizona Gazette reported that an explorer named G. E. Kinkaid had discovered a vast underground citadel inside the canyon, filled with artifacts linked to ancient Egyptian civilization. He even claimed the expedition had been funded by the Smithsonian.

This story described hieroglyphics on the walls, mummies in the chambers, and relics pointing to a direct connection with the Egypt of the pharaohs. It was incredibly detailed, and it was, of course, a hoax. No evidence for any of Kinkaid's claims ever surfaced.

5

Fewer than 100 people have ever hiked its full length

Among the few people who have completed the through-hike of the Grand Canyon is Jen Hogan, the first woman to accomplish it, finishing her journey in 2021–2022.

It’s a full 800-mile length below the rim. The route involves extreme heat, flash floods, near-impassable areas, and stretches with no water or trail whatsoever. Around 60 or 70 people have reportedly accomplished it. This makes it one of the most exclusive feats on Earth.

6

The Grand Canyon's rocks predate dinosaurs entirely

Visitors scanning the canyon walls for fossils are often surprised to learn they won't find any dinosaur bones here. The rock layers of the Grand Canyon are simply older than dinosaurs. This fact alone can be shocking: staring at its walls means staring at marine fossils from as far back as 1.2 billion years ago. Some of its caves hold the remains of ancient mammals. The canyon is a window into a world that existed long before the dinosaurs, when the land that is now Arizona lay beneath a shallow sea.

7

The park is bigger than Rhode Island

Numbers alone rarely capture the Grand Canyon's scale, so here's a different approach. Rhode Island covers about 1,214 square miles, and the Grand Canyon National Park spans 1,904 square miles.

The canyon's depth exceeds four Empire State Buildings (which is 1,454 feet) stacked on top of one another. That’s 6,093 feet at its deepest point.

8

But it's not the deepest canyon on Earth

For all its grandeur, the Grand Canyon does not hold the depth record. Pictured above, the Yarlung Tsangpo Grand Canyon in Tibet, China, plunges to 17,567 feet, which is nearly three times deeper. Carved by the Yarlung Tsangpo River as it cuts through the eastern Himalayas, that canyon is so remote and extreme that it remained largely uncharted until the late 20th century.

9

It is home to a pink rattlesnake found nowhere else on Earth

The Grand Canyon Pink Rattlesnake has a pinkish-red coloring that matches the canyon's own distinctive rock walls so closely that it's nearly invisible. It is found nowhere else in the world. Officially classified as Crotalus oreganus abyssus , it has darker diamond-shaped markings along its back that deepen the camouflage further.

10

There's a village at the bottom: Supai Village

For over 1,000 years, the remote village of Supai has been home to the Havasupai Tribe, the People of the Blue-Green Waters. It is located an eight-mile hike from the rim, but sits roughly 3,000 feet deep inside the Grand Canyon.

The U.S. Department of Agriculture has called it the most remote community in the contiguous United States, and it has no automobiles and no road access. The only ways in are on foot, by mule, or by helicopter. It is also the only place in the United States where the postal service still delivers mail by mule train.