Geography Geography 5 min read

Stories carved by the Colorado River

The missing pieces of the Grand Canyon: 10 incredible facts

Image: jesus esteban

The Grand Canyon is bigger than Rhode Island. It's deeper than four Empire State Buildings stacked end to end. Its rocks are older than dinosaurs. But those stats alone don’t quite capture its immensity — and are hardly the most shocking. There are nuclear shelters, hidden villages, and billion-year mysteries involved. Read on to learn 10 lesser-known facts about the Grand Canyon.

1
There's an unexplained billion-year gap

Image: John Graybosch

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

Image: Lauri Väin from Tallinn, Estonia, CC BY 2.0, via Wikimedia Commons

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

Image: Alexandre Henry Alves

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The disaster exposed a terrifying truth: the U.S. air traffic control system was dangerously outdated, relying on pilots' visual estimates and rough guesswork from controllers , with no way to separate fast-moving aircraft from slow ones, or instrument-flying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

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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

Image: Abhishek Navlakha

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

Image: MARIOLA GROBELSKA

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

Image: AussieActive

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

Image: Naeemphotographer2

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

Image: Alexander Wong

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

Image: joojoob27

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.

Geography Geography 4 min read

Discovering America

What's the easternmost point of the US? If you say Maine, think again!

Image: Jon Sailer

We’ve all picked up "facts" about the fifty states somewhere along the way, but not all of them hold up. Some are half-truths passed around for generations , others are just plain wrong. So, in an attempt to set the record straight once and for all, we’ve gathered some fun truths that clear up the biggest mix-ups about our states.

1
Arizona skips Daylight Saving Time

Image: Christoph von Gellhorn

This is partly true because most of the state doesn’t bother with Daylight Saving Time . They stopped changing the clocks back in 1967. The exception is the Navajo Nation, which stretches into Utah and New Mexico and keeps DST so all its communities stay on the same schedule. Now, as for the smaller Hopi reservation, inside the Navajo Nation, it sticks with Arizona time… Yes, quite confusing if you’re not a local.

2
Georgia isn’t really the Peach State

Image: Jessica Furtney

Georgia loves its peaches, sure, but the state’s top fruit money-maker is actually blueberries . In recent years, blueberries have brought in several times more cash for farmers than peaches. Meanwhile, California grows far more peaches than Georgia ever has. The nickname stuck from the old days when Georgia peaches were famous for their flavor, not their volume. So while the pride is real, the peaches aren’t quite the powerhouse people may think.

3
Nevada didn’t record the hottest US temperature

Image: tommao wang

You probably think of Nevada’s desert heat as unmatched, but the all-time record belongs to California’s Death Valley . In July 1913, it hit a mind-melting 134 degrees Fahrenheit, the hottest temperature not only in America but the hottest ever recorded on Earth!

4
Minnesota doesn’t have the most lakes

Image: Tom Conway

Minnesota proudly calls itself the "Land of 10,000 Lakes," but that’s selling itself short… The real number is closer to 12,000. However, Alaska wins this battle . The state has more than 3 million lakes over five acres in size. In fact, Alaska contains over 40 percent of the nation’s surface water. If you love fishing, kayaking, or just staring at a quiet stretch of water, the true lake capital of America is far up north.

5
Pineapples aren’t native to Hawaii

Image: Christian Joudrey

Pineapples are everywhere in Hawaiian imagery, but the plant actually comes from South America , mainly Paraguay and southern Brazil. Spanish explorers likely brought them to Hawaii in the 1500s after spreading them across the Pacific to places like the Philippines and Guam. Hawaii’s climate turned out to be perfect for growing them and by the 1900s, the islands were producing so many pineapples that the fruit became a symbol of Hawaii itself.

6
Maine isn’t the country’s easternmost point

Image: Chris Henry

If you’re a Geography geek, you’ll love this one. You might picture Maine’s rocky coast as the eastern tip of America, but the actual easternmost point is thousands of miles away, on Alaska’s Semisopochnoi Island in the Aleutians. How is that possible? Well, that’s because it crosses the 180th meridian, putting it in the Eastern Hemisphere. That means part of Alaska technically sits farther east than anywhere in Maine.

7
The biggest US earthquake didn’t happen in California

Image: Lala Miklós

California has suffered some big earthquakes in its history, but the most powerful earthquake in America struck Alaska in 1964 . It hit Prince William Sound with a magnitude of 9.2. It was so strong it shook the ground for four and a half minutes and triggered massive tsunamis. In today’s dollars, the damage would total more than $2 billion. Alaska sits on a collision zone of tectonic plates, making it one of the world’s most seismically active regions.

8
The Everglades isn’t America’s biggest swamp

Image: Joshua J. Cotten

A lot of people picture the Florida Everglades when they think of swamps, but technically, the Everglades isn’t a swamp at all. The real title of the largest swamp in the United States goes to Louisiana’s Atchafalaya Basin , which spans about 1.4 million acres. This swamp has a vast mix of cypress forests, bayous, and marshes, and it’s more than twice as productive as the Everglades when it comes to wildlife and plant life.

9
Big cities aren’t always capitals

Image: Mackenzie Cruz

It surprises people how often the biggest city isn’t the state capital . New York City? Not the capital… Albany is. Chicago? Nope, that honor goes to Springfield. Pennsylvania’s capital isn’t Philly or Pittsburgh, it’s Harrisburg. Even California’s capital isn’t L.A. or San Francisco, it’s actually Sacramento. Out of fifty states, only seventeen have their most populous city as the capital.

10
Alaska isn’t divided into counties

Image: Rod Long

Alaska likes to do things its own way. Instead of counties, it’s split into boroughs , and a massive area known as the Unorganized Borough has no local government at all. People out there don’t pay property taxes, but that freedom comes with challenges, limited services, fewer job options, and tough living conditions.

Culture Culture 6 min read

The Five-Sided Puzzle Palace

A man lived there secretly? Stunning facts about the Pentagon

Image: Touch Of Light, CC BY-SA 4.0, via Wikimedia Commons

Did you know that construction on the Pentagon building began on September 11, 1941, exactly 60 years before it was attacked? The home of the US Department of Defense has stood for more than 80 years. Although its iconic shape is intriguing in itself, it hides deeper secrets that many Americans have never heard of. Did you know it feeds 26,000 people a day—at a McDonald's, a Five Guys, a Taco Bell, and over 30 other restaurants? Or that a man secretly lived inside its walls for years? Let’s dive into the Pentagon building’s secrets.

1
A renovation project saved thousands of lives on 9/11

Image: Office of the Secretary of Defense - Public Affair, Public domain, via Wikimedia Commons

On September 11, 2001, American Airlines Flight 77 struck the Pentagon at 9:37 a.m., killing 189 people. Few people know this part: the death toll could have been much higher. But there was a renovation project underway at the time of the attacks.

The Pentagon’s five-sided structure is divided into five "wedges," and workers had been renovating them one at a time. Flight 77 struck the wedge that had just been completed. Of the 4,500 people who normally worked in that section, only about 800 had moved back in. Without the reinforced construction and the incomplete occupancy, experts believe the casualties would have been catastrophically higher.

2
The Cold War and the hot dog stand

Image: Anete Lusina

In the middle of the Pentagon’s five-acre center courtyard once stood a modest hot dog stand. According to a Cold War legend (one still retold by official Pentagon tour guides on every public tour), between the 60s and the 80s, Soviet satellite images tracked large groups of high-ranking military officials converging on that small building at the same time every day.

Soviet intelligence reportedly concluded the structure must be the entrance to some underground bunker in America. In reality, all it did was sell lunch. In 2006, the original stand was torn down, and a sandwich shop was built in its place.

3
Its construction began on September 11th, exactly 60 years before the attack

Image: Aber, Marilyn K., Public domain, via Wikimedia Commons

Builders broke ground on the Pentagon on September 11, 1941. That was exactly 60 years to the day before the September 11, 2001, terrorist attacks that would strike the same building.

Construction had been ordered by Army Brigadier General Brehon Somervell, who wanted a permanent headquarters for the Defense Department to replace its then-17 scattered offices across Washington, D.C.

The project was extraordinarily ambitious: plans called for the world’s largest office building to be completed in just 16 months. In the end, the conception, design, and construction of the entire Pentagon building took a total of 15 months.

4
The same person oversaw its construction and the Manhattan Project

Image: U.S. Army, Public domain, via Wikimedia Commons

Colonel Leslie Groves of the Army Corps of Engineers took charge of Pentagon construction in August 1941. He worked six days a week and drove his team relentlessly, at one point employing more than 15,000 workers around the clock.

When the Pentagon was finished in January 1943, Groves was assigned to lead the Manhattan Project, America’s secret program to build the atomic bomb . His deputy, Captain Robert Furman, followed him into the Manhattan Project as chief of foreign intelligence. Together, the men who built the world’s largest office building went on to produce the weapon that ended World War II.

5
Why is it shaped like that?

Image: Boston Public Library, CC BY 2.0, via Wikimedia Commons

The Pentagon’s iconic five-sided shape was the consequence of a geographic accident. The original site selected for the building, near Arlington Cemetery, **happened to be bordered on five sides by roads. **Architects designed the structure to fit those boundaries, producing a pentagonal floor plan. Then President Franklin D. Roosevelt intervened: worried the massive building would obstruct the view of Washington, D.C. from Arlington, he ordered the site moved to its current location along the Potomac River. But the five-sided design had already been drawn up, and nobody changed it.

6
It was the first desegregated building in Virginia

Image: https://ddotlibrary.omeka.net/items/show/100, Public domain, via Wikimedia Commons

When the Pentagon was designed in 1941, segregation was the law in Virginia. Original plans called for doubled bathroom facilities: separate ones for Black and white employees, as required by Virginia statute. But President Roosevelt had signed Executive Order 8802 in June 1941, prohibiting racial discrimination in federal employment and government contracting.

As a federal building, the Pentagon was exempt from Virginia law. It became the only building in the state where segregation was not enforced. A fully desegregated federal workplace that opened in 1943. The doubled bathrooms were built anyway, as the plans were too far along to revise, but were never used as separately designated spaces.

7
Its construction was surprisingly frugal and incredibly fast

Image: See page for author, Public domain, via Wikimedia Commons

Ground broke on September 11, 1941, and construction finished on January 15, 1943, just 16 months later. More than 15,000 workers were on site around the clock. Wartime office shortages were so severe that employees moved into completed wings before the rest of the building was finished. Steel was too scarce to use extensively, so builders relied almost entirely on reinforced concrete. The 689,000 tons of sand and gravel required came directly from the nearby Potomac River, cutting transportation costs. The project was budgeted at $35 million, but the final bill was $63 million, which would translate to over $900 million in today’s dollars.

8
You can walk between its farthest points in only 7 minutes

Image: Bea A Carson, CC0, via Wikimedia Commons

The Pentagon is the world’s largest low-rise office building: 6.5 million square feet of space, which is three times the total floor area of the Empire State Building. Each of its five outer walls is 921 feet long. It has 7,754 windows and 17.5 miles of corridors. Approximately 26,000 military and civilian employees report for work there every day.

Despite that scale, the building’s concentric ring design is so efficient that it takes only about seven minutes to walk between its two farthest points.

9
The man who secretly lived inside its walls

Image: Carol M. Highsmith, Public domain, via Wikimedia Commons

During construction, Colonel Groves drove his deputy, Captain Robert Furman, so relentlessly that Furman rarely left the building. To cope, Furman had contractors build him a small, windowless apartment hidden inside the walls of the Army’s Ordnance Division. In this private room, he could sleep and shower without leaving the premises.

When construction ended and personnel dispersed, knowledge of the hidden room was never passed on to building management. Months later, when Furman returned to Washington on Manhattan Project intelligence business, he found the apartment undiscovered and exactly as he’d left it.

For over a year, he would slip back to the Pentagon, pop open a wall panel, spend the night, and emerge in the morning with his suitcase. He was finally caught in 1943 and forced to surrender the keys. It was never disclosed whether the secret apartment was maintained or eventually absorbed back into the official floor plans.

10
It houses over 30 restaurants, including everyone's favorite chains

Image: Harrison Keely, CC BY 4.0, via Wikimedia Commons

The Pentagon feeds roughly 26,000 people a day, and its dining options read less like a military headquarters and more like a mall food court. The main Concourse Food Court, which opened in September 2009 and seats 875 people, is the largest of several dining areas.

Confirmed chains currently inside the building include McDonald’s, Five Guys, Subway, Popeyes, Starbucks (multiple locations), Dunkin’ (two locations), Panera Bread, Taco Bell, Panda Express, Baskin-Robbins, Potbelly, Jamba Juice, and Moe’s Southwest Grill, among others. The building also houses a CVS pharmacy, a florist, a jeweler, and a dry cleaner. In the summer of 2024, Potbelly became the first restaurant to open in the center courtyard. Yes, the very spot where the legendary Cold War hot dog stand once stood.

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