The ancient Egyptians built prototypes of the modern Suez Canal

The US finished what the French had started with Panama's canal

For about two decades, Suez Canal-builder and Frenchman Ferdinand de Lesseps led the project, but financial troubles forced it into the hands of the US, who completed it in 1914. This timeline, made to accompany the definitive PBS American Experience documentary about the canal, highlights major moments in its construction.

Maritime trade in the Mediterranean accelerated during the late Bronze Age

This map illustrates the vibrant trade networks of the eastern Mediterranean during the Late Bronze Age (circa 1500–1200 BCE), highlighting an era of growing interconnectivity among major powers including Egypt, the Hittite Empire, Mesopotamia, and others.

The Erie Canal remains open to modern boaters

Nearly two centuries after its completion, the Erie Canal is still navigable. Each year, thousands of recreational vessels traverse its 339 miles of waterways—passing through historic towns, beautiful scenery, and restored locks.

Ancient Egypt began as a collection of independent city-states along the Nile

Those cities were gradually organized into Upper and Lower Egypt, names derived from the northern flow of the river. The region was unified for the first time in 3,100 BCE under King Menes (also known as Narmer).

The Greek city of Alexandria in Egypt helped form the template for modern cities

It was designed by Dinocrates, who studied under Hippodamus, the father of urban planning. Hippodamus preached that urban planning should take into account function, culture, and politics. Dinocrates' design of Alexandria meant applying Hippodamus' teachings on a scale never before attempted.

A pottery jar from the Naqada II period is the oldest depiction of a sailboat

The Egyptian artifact, made by the Gerzeh culture from 3650 BCE to 3300 BCE, provides the earliest evidence of humans harnessing wind power in a technological capacity.

The Silk Road was an ancient series of trade routes between East Asia and Europe

Founded by the Han Chinese in 130 BCE, the Silk Road was a series of trade routes connecting eastern China with the Mediterranean and the rest of Europe. The Persians created a predecessor series of routes, but the Chinese solidified the Silk Road, where travelers traded commerce, ideas, and more.

Ancient Greece originated roughly 4,000 years ago around the Aegean Sea

From architectural feats to the Western alphabet, ancient Greece has helped shape modern life. Over centuries, the eastern Mediterranean culture grew as far as India, Egypt, and Spain. Its cultural influence has long since spread beyond any physical boundaries.

Roughly 25,000 workers died building the canal

For each mile of canal that was built, 500 workers lost their lives. The threats came from multiple fronts: mudslides, floods, earthquakes and disease-carrying mosquitoes. Workplace accidents became so common that artificial limb manufacturers competed for contracts with the canal builders.

Estimate the costs of an ancient Roman vacation

Thanks to a sophisticated system of roads, Romans could travel great distances for their Roman holidays. This interactive resource from Stanford allows you to create fictional journeys around the empire, seeing approximate routes, costs, and time.

Watch the history of human migration that led to civilizations

Starting in Africa where they hunted with spears and fires, humans would gradually move out of the continent over thousands of years as they navigated crossing deserts, rivers, uneven terrain, and shifting climates. Development of technology, language, farming, and other societal structures helped build up the first civilizations.

Inside Saqqara, ancient Egypt's sprawling necropolis outside Memphis

Located 20 miles south of modern-day Cairo, the 4-square-mile site contains the oldest known stone complex in the world, the venue for royal tombs and monuments for one of the earliest Egyptian capitals, Memphis.

The three theories explaining how the pyramids were built

There's no consensus over how the ancient monuments were built, and no blueprints left behind. But centuries of study have produced three competing theories: a simple, massive external ramp, a more complex internal ramp, or a highly sophisticated water elevator.

Greek-Egyptian scientist Heron invented automatic doors for a temple

The doors opened when a fire was lit in front of the temple, causing heat and pressure to build in a nearby vessel that would force its contents into a higher secondary vessel. This secondary vessel would lower, pulling the doors open. When the fire extinguished, the pressure and liquid in the vessel would reverse course, closing the temple doors.

Why pickles became a thing

Pickles began in Mesopotamia around 2400 BCE as a way to preserve vegetables amid heat (and spoilage). They spread through Egypt, Greece, and Rome, where Julius Caesar reportedly fed pickles to his soldiers, and brining was treated as a culinary art. The technique is broadly useful, as salt and water can extend the shelf life and deepen flavor for almost anything.

The aqueducts and cisterns of Constantinople

The system of aqueducts that supplied Byzantine Constantinople with water had more than 500 kilometers of channels. These channels fed hundreds of cisterns. The largest were open pools (one, now drained, houses an entire modern shopping center); but the most impressive were vast covered chambers like the Basilica Cistern, still a highlight of any visit to Istanbul.

A bankrupt flour merchant in debtor’s prison helped inspire the Erie Canal

In 1807, Jesse Hawley, jailed for debt after struggling with high transport costs, published essays under the pen name “Hercules.” His writings laid out the canal’s route and benefits, galvanizing support for the project.

The Rosetta Stone helped scholars decipher Egyptian hieroglyphics

With the same verses written in three languages, the stone—discovered during Napoleon's campaign in Egypt—let scholars decipher hieroglyphics for the first time, unlocking the secrets of ancient Egypt. Learn why the task, originally expected to take two weeks, ended up taking 20 years with this fascinating essay.

The 1956 Suez crisis was one of the earliest tests of the rules-based order

When Britain, France, and Israel secretly invaded Egypt, the Eisenhower administration supported UN resolutions condemning the invasion and called for a ceasefire—publicly criticizing its closest allies to uphold the principle that force should not be used to resolve international disputes.

Earth's circumference was estimated over 2,000 years ago using geometry and shadows

By measuring the angle of the shadow cast in Syene when no shadow was cast in Alexandria, Eratosthenes used the distance between the two cities and trigonometry to estimate the Earth's circumference to within a few percentage points of the actual value.

The National Mall once had canals and rail lines

In the 1800s, the National Mall looked nothing like it does today. Canals, rail lines, markets, and industrial uses crisscrossed the Mall before later redesigns cleared it into a unified civic landscape.

Stanford built a Google Maps for the Roman Empire, revealing how much it cost to travel in the ancient world

Egyptians called the Nile River the 'Ar,' meaning 'black'

The over 4,000-mile river would turn dark during its warm-season flooding as sediments flowed downriver. This nutrient soil, which would settle on the riverbank, was essential for farming in Egypt.

Ancient Egyptians developed the first pregnancy test—and scientists tested it in the 1960s

A papyrus from about 1350 B.C.E. discusses a test in which a woman would urinate on wheat and barley seeds over the course of several days. If the barley grows, she's having a male child; if the wheat grows, it's a female child; and if nothing grows, she's not pregnant. Scientists went on to test this theory in 1963 and found that about 70% of the time, the urine of pregnant women did promote growth whereas the urine of nonpregnant women didn't—perhaps due to estrogen levels in the urine.

The idea of a check—or promissory note—goes back to antiquity

As long as traders have looked to pay in cash or coin, the idea of an IOU has been close behind. Clay tablets from ancient Mesopotamia (roughly modern Iraq) and Persia (Iran) suggest proto-checks were used at the time. Islamic traders innovated "sakks" in the 9th century, leading to the broader adoption during the Middle Ages in Europe.

The archaeological sites uncovered through London's Crossrail Project

The Crossrail Project is an underground train system in London, which saw 26 miles of new tunnels created over more than a decade. The project provided unique access to long-buried layers of London's history, and a massive parallel archaeological excavation took place.

In 1963, a basement renovation in Turkey revealed a passageway to a hidden, multilevel underground city that once housed as many as 20,000 people

Graffiti dates back to at least ancient Pompeii, where citizens scrawled messages to one another on public walls

In its famous catalog, Sears sold $600 DIY house kits from 1908 through the 1940s, resulting in an estimated 100,000 'Sears and Roebuck homes.'

See a 3D reconstruction of Tenochtitlan, the Aztec capital that was home to an estimated population of 200,000 to 400,000.

In 1915, workers recovered a submarine-like vessel from the Chicago River, prompting fears of German espionage

Visualize the path of every solar eclipse from 1900 to 2099 and see what each looks like when observed from different locations on Earth.

Learn more about the history of fireworks, which dates back to an accidental invention during an alchemist's quest for information about immortality.

For centuries, it was common to sleep in two shifts: a few hours at the beginning of the night, and a longer period beginning around midnight

The US Constitution is widely regarded as the longest-standing written national constitution still in force—see how it has influenced rights worldwide.

Volcanic activity may have triggered the Black Death by spewing gases that led to crop failures in Europe, thus forcing the import of grain ships with plague-infested fleas.

For centuries, Niagara Falls has been a magnet for daredevils seeking to conquer one of nature's most powerful wonders, with its 200-foot drop and water rushing at 32 feet per second with 280 tons of force.

The Great Salt Lake's distinct dual coloration results from high-salinity organisms that only live in the northern portion and produce a purple protein.

The term 'algorithm' originated from the Latinized name of al-Khwārizmī, a 9th-century mathematician whose works introduced Arabic numerals and the decimal-based numeral system to Europe and whose treatise 'Al-Jabr' gave algebra its name.

Artificial coral reefs have been 3D printed from nontoxic, biodegradable terracotta clay, which coral polyps have used as a foundation for rebuilding marine ecosystems.

Scientists can determine Earth's past climate conditions by analyzing air trapped in microscopic bubbles within ice cores—columns of compressed snow layers that build up over hundreds of thousands of years.

Take a 3D tour of the Hajj, Islam's annual pilgrimage to Mecca, undertaken by over 1.5 million Muslims.

The American cockroach is actually from Africa, an apparent hitchhiker aboard ships carrying enslaved people, with evidence suggesting the bug may have arrived in the New World as early as the 1600s.

The Mona Lisa's celebrity status and repeated restorations have obscured what made the painting so revolutionary for its time

The American Society of Civil Engineers' infrastructure report card gave the US a C in 2025, its highest grade since the project launched in 1998.

Long before Major League Baseball began allowing instant replay for balls and strikes, an umpire reluctantly used the technology to determine whether a hit was a home run, a move that inadvertently ushered in a new era for the sport.

Sunflowers have long been a symbol of nuclear disarmament because they can extract large amounts of radioactive cesium from soil.

Some coin denominations have ridges etched on their sides, partly to prevent counterfeiting, in a practice called 'reeding.'

See the evolution of Ebola vaccine and treatment development.

When you complete a CAPTCHA on a website to prove you are human, you may be unknowingly training algorithms for self-driving cars, whose systems require training data to help identify crosswalks, bicycles, and other outdoor objects.