The Antikythera Mechanism Is a 2,000-Year-Old "Computer" From Ancient Greece

The Antikythera Mechanism is one of the most astounding archaeological finds in history. Discovered within the ruins of an ancient Greco-Roman shipwreck in 1900, it was brought to the surface the following year as part of the world’s first major underwater archaeological excavation. Initially, the mechanism — in dozens of corroded, greenish pieces of bronze — was overlooked in favor of the many bronze and marble statues, coins, amphorae, and other intriguing items the shipwreck contained. But in the 1950s, science historian Derek J. de Solla Price took particular interest in the machine, convinced that it was in fact an ancient computer. In the early 21st century, advanced imaging techniques proved Price correct.

Of course, this is an analog computer we’re talking about, not a digital one. About the size of a mantle clock, the Antikythera Mechanism was a box full of dozens of gears with a handle on the side. When the handle turned, the device calculated eclipses, moon phases, the movements of the five visible planets — Mercury, Venus, Mars, Jupiter, and Saturn — and more. It even included a dial for the timing of the ancient Olympics and religious festivals. Nothing else like it is known from antiquity (the machine has been dated to around the first century BCE), and nothing like it shows up in the archaeological record for another 1,000 years. Scientists aren’t sure exactly who made the device, although the ancient Greek astronomer and mathematician Hipparchus has been suggested as the creator, and the famed mathematician and inventor Archimedes may also have been involved. While its origin will likely remain a mystery, the mechanism’s purpose has grown clearer with time — and its existence has completely altered our understanding of the history of technology.

The Ancient Egyptians Invented Toothpaste

The ancient Egyptians are known for many firsts. Hieroglyphics, papyrus, the calendar, and even bowling all come from the minds of the ancient people along the Nile. Egyptians were also some of the first to pay particular attention to oral care. They invented the first breath mint, toothpicks have been found alongside mummies, and they created the oldest known formula for toothpaste.

One of the earliest medicinal texts, the Ebers Papyrus, contains an astoundingly accurate understanding of the human circulatory system as well as an assortment of medicinal remedies. Written around 1550 BCE, this ancient text also describes a very old form of toothpaste. This early dentifrice was likely made from ingredients such as ox hooves, ashes, burnt eggshells, and pumice (a type of volcanic rock), but by the fourth century CE, when Egypt was under Roman rule, the recipe evolved to include salt, pepper, mint, and dried iris flower, based on descriptions in another papyrus. Egyptians may have applied the paste with toothbrushes made from frayed twigs.

The World’s Oldest Mummies Are in Chile

Egypt may be home to the world’s most famous mummies, but not the world’s oldest. That distinction belongs to Chile, where mummified remains predate their Egyptian counterparts by more than 2,000 years. Known as the Chinchorro mummies, these artificially preserved hunter-gatherers were first discovered just over a century ago in the Atacama Desert, the driest nonpolar desert in the world. Their relatively recent discovery is perhaps explained by the fact that they weren’t buried in ostentatious pyramids but rather — after being skinned and refurbished with natural materials — wrapped in reeds and placed in shallow, modest graves. It’s estimated that the oldest Chinchorro mummies date back 7,000 years. Some are now in museums, while others remain underground in land currently threatened by climate change, as rising humidity levels alter the famously dry conditions of the desert. UNESCO added the Chinchorro mummies and the settlement where they were found to the World Heritage list in July 2021, and a museum devoted to them has been developed in the northern port city of Arica, with plans to expand it.

The Easter Island Heads Have Bodies

Few historical artifacts are as mesmerizing — or as mysterious — as the Easter Island statues. Known as moai (pronounced “mo-eye”), meaning “statue” in Rapa Nui (the Native name for the island, its Indigenous people, and their language), the statues are believed to represent ancestral chiefs who protected the inhabitants of this 63-square-mile island in the Pacific centuries ago. Possibly built between 1400 and 1650 CE, the statues were transported to massive stone platforms known as ahu, and usually arranged so their backs faced the sea. Although their average height is only around 13 feet (bodies and heads included), many weigh more than 10 metric tons.

Most of the 900 or so moai aren’t buried, and when Europeans first arrived in the early 18th century, they could clearly see their bodies standing tall. But the 150 or so that are buried have become the most popular and photogenic. Resting on the slopes of the Rano Raraku volcanic crater (which is also the stone quarry for the statues), these moai were slowly entombed by continuous erosion and landslides over hundreds of years until only their heads remained. Luckily, this unintended burial preserved their tattoo-like markings, a strong tradition among the Rapa Nui people.

The Aztecs Considered Cacao Beans More Valuable Than Gold

You may love chocolate, but probably not as much as the Aztecs did. This Mesoamerican culture, which flourished in the 15th and early 16th centuries, believed cacao beans were a gift from the gods and used them as a currency that was more precious than gold. The biggest chocoholic of them all may have been the ninth Aztec emperor, Montezuma II (1466–1520 CE), who called cacao “the divine drink, which builds up resistance and fights fatigue. A cup of this precious drink permits a man to walk for a whole day without food.” To say he practiced what he preached would be an understatement: Montezuma II was known to drink 50 cups of hot chocolate a day (from a golden goblet, no less). His preferred concoction is said to have been bitter and infused with chiles.

Needless to say, that was an expensive habit. Aztec commoners could only afford to enjoy chocolate on special occasions, whereas their upper-class counterparts indulged their sweet tooth more often. That’s in contrast to the similarly chocolate-obsessed Maya, many of whom had it with every meal and often threw chile peppers or honey into the mix for good measure.

Vikings Didn’t Really Wear Horned Helmets

Aside from long blond hair, horned helmets are probably the most famous Viking accessory — but that would have been a surprise to the real Scandinavian warriors who plundered Europe between the ninth and 11th centuries. The Viking horned helmet convention dates only to the 19th century: In 1876, costume designer Carl Emil Doepler introduced it in Richard Wagner’s famous opera “Der Ring des Nibelungen” (“The Ring of the Nibelung,” often called the “Ring Cycle”). At the time, Germans were fascinated with the story of the Vikings, so Doepler plopped the ancient headdress of the Germans — the horned helmet — on Wagner’s Viking protagonists. The opera proved so popular that by 1900 the horned helmet was inextricably entwined with Vikings themselves, appearing in art, ads, and literature.

Yet during the Viking era, Norse warriors never actually wore horned helmets — and especially not during battle, where they’d probably have gotten in the way. Some artifacts, such as a tapestry discovered with the famous Oseberg ship burial in 1904, do depict horned figures, but these “horned” occurrences only happened — if they happened at all — during rituals. To date, archaeologists have uncovered only two preserved Viking helmets: Both are made of iron, both have guards around the eyes and nose, and both are entirely without horns.

Cleopatra Lived Closer to the iPhone’s Debut Than to the Building of the Pyramids at Giza

When we think about nations and empires, we’re usually thinking in terms of centuries, but ancient Egypt stretched on for three millennia. The empire’s first pharaoh, Menes, united the country and formed the first dynasty on the Nile around 3100 BCE. Nearly 500 years later (more than double the entire history of the United States), the first of the Great Pyramid’s 2.3 million stone blocks was put into place. These blocks were the beginnings of an illustrious tomb for the Fourth Dynasty Pharaoh Khufu. Within the next century, two other pyramids (along with an equally impressive sphinx) were completed nearby. Today, the three Pyramids of Giza are regarded as the oldest — and the only surviving — of the Seven Wonders of the World.

It wasn’t until about 2,500 years after that first block was wedged into place that Cleopatra VII was born, around 69 BCE. Although the world of Cleopatra feels more comparable to the ancient reign of Khufu than the technological reign of the iPhone, first introduced in 2007, she’s about 400 years closer to our own age than to the creation of Egypt’s most famous wonders — which have now been standing for an incredible 4,500 years.

The World’s First Vending Machine Dispensed Holy Water

Democracy, theater, olive oil, and other bedrocks of Western civilization all got their start with the Greeks. But even some things that might seem like squarely modern inventions have Hellenistic roots, including the humble vending machine. In the first century CE, Greek engineer and mathematician Heron of Alexandria published a two-volume treatise on mechanics called Pneumatica. Within its pages were an assortment of mechanical devices capable of all types of wonders: a never-ending wine cup, rudimentary automatic doors, singing mechanical birds, various automata, the world’s first steam engine, and a coin-operated vending machine.

Heron’s invention wasn’t made with Funyuns and Coca-Cola in mind, however: It dispensed holy water. In Heron’s time, Alexandria was a province of the Greek empire and home to a cornucopia of religions, with Roman, Greek, and Egyptian influences. To stand out, many temples hired Heron to supply mechanical miracles meant to encourage faith in believers. Some of these temples also had holy water, and experts believe Heron’s vending machine was invented to moderate acolytes who took too much of it.

The mechanism itself was simple enough: When a coin was inserted in the machine, it weighed down a balancing arm, which in turn pulled a string opening a plug on a container of liquid. Once the coin dropped off the arm, the liquid stopped flowing. It would be another 1,800 years before modern vending machines began to take shape — many of them using the same principles as Heron’s miraculous holy water dispenser.

Jericho Is Likely the Oldest Continuously Inhabited City in the World

Although scenic metropolises like Toronto and Vienna may top the rankings of greatest cities to call home, these urban centers have nothing on Jericho when it comes to historical charm. After all, this Middle Eastern oasis has hosted human residents for at least 11,000 years, making it likely the oldest continuously inhabited city in the world.

Thanks in large part to the nearby water supply now known as Elisha’s Spring (or Ein es-Sultan), nomadic hunter-gatherers began settling these fertile grounds as the Mesolithic Period drew to an end, perhaps around 9000 BCE. By around 8300 BCE, inhabitants had already constructed a bordering wall of stone, along with a 28-foot tower that may have served as a cosmological marker. Although the initial colony of 2,000 to 3,000 inhabitants had dissipated by 7000 BCE, subsequent communities sprung to life as residents continued to hone agricultural techniques, with each settlement building on top of the previous one. Altogether, some 23 layers of civilizations have been uncovered in the area.

The Incas Developed Their Own Postal System

The Inca Empire was a powerful pre-Columbian civilization that once covered almost the entire west coast of South America. By 1471, the empire stretched for more than 3,400 miles, and was the largest empire in the world at the time, including European nations. The Incas built a vast network of roads that stretched for more than 25,000 miles, and used llamas as their beasts of burden.

Because their empire was so large and intricate, the Incas had to come up with a way to quickly and efficiently spread messages throughout the land. Chaski were the postal carriers of the Inca Empire. They were trained runners who could collectively cover up to 150 miles per day. The runners worked using a relay system — the first chaski ran 6 to 9 miles until he reached a small house, called a chaskiwasi, where another runner waited to complete the next leg of the journey. They used the extensive road network and specialized rope bridges to quickly move through the empire.

The Great Wall of China Was Built With Porridge in the Mortar

Traversing thousands of miles across eastern Asia, the Great Wall of China has stood as a symbol of the country’s military and technological know-how for more than 2,000 years. And thanks to a team of scientists at Zhejiang University, we now know that the secret to its legendary endurance is … sticky rice soup?

As explained in Accounts of Chemical Research in 2010, the scientists stumbled upon this discovery while examining mortar samples from the Great Wall and other long-standing Chinese buildings. They realized the mortar was an unusual composite created from slaked lime and congee, the former a heated type of limestone exposed to water, and the latter a pudding-like rice porridge commonly eaten throughout Asia. When combined with the lime’s calcium carbonate, a complex carbohydrate in the congee known as amylopectin helped stymie the development of calcium carbonate crystals in the mortar, resulting in a compressed structure that gave the ancient barrier the strength to withstand earthquakes and bulldozers. While not invented until around the fifth century CE, well after the initial parts of the Great Wall were raised, the sticky rice-lime mortar was used for the well-preserved sections that remain from the Ming dynasty (the 14th through 17th centuries).

Beer Dates Back at Least 5,000 Years

Beer is as old as history — and by some counts, even older. Many experts assert that the emergence of Sumerian cuneiform in the fourth millennium BCE marks the beginning of recorded history. The first hard evidence of beer brewing also comes from the Sumerians of Mesopotamia, in a town called Godin Tepe (now part of Iran). In 1992, archaeologists there discovered traces of beer in jar fragments dated to around 3500 BCE. However, some scholars suggest that beer is as old as grain agriculture itself — which would put the boozy beverage’s invention at around 10,000 BCE, somewhere in the Fertile Crescent.

Strangely (or not), thousands of Sumerian tablets make mention of beer. In fact, it even makes an appearance in the Epic of Gilgamesh, often regarded as the oldest surviving piece of literature. But among all these references, no recipes for this ancient brew were ever recorded. The closest thing to step-by-step instructions is a text known as the Hymn to Ninkasi (aka the goddess of beer). Written around 1800 BCE, this hymn describes the malts, cooked mash, and vats used in the beer-making process. It seems that Sumerian beer had mostly two ingredients: malted barley and beer bread, or bappir, which introduced yeast for fermentation. The beer was then drunk from communal jars, and its sediments were largely filtered out by drinking the concoction from reed straws.

Some of the Stones at Stonehenge Came From 150 Miles Away

Questions abound when it comes to Stonehenge, but not everything about the monument is shrouded in mystery. We know, for instance, that around 100 stones make up the site — and that some of them came from nearly 150 miles away. Given that Stonehenge is 5,000 years old, that’s quite the feat. This raises two crucial questions: Who transported said stones, and how? That’s where the mystery begins. For one thing, no one’s sure who built England’s world-famous monument, with everyone from Merlin to aliens receiving credit from various factions; more plausible culprits include Danes, Celts, and Druids.

The stones at Stonehenge are grouped into two types: larger blocks known as “sarsen stones,” and smaller stones in the central area known as “bluestones.” Over the last decade or so, researchers have confirmed that the bluestones came from the Preseli Hills of western Wales, about 150 miles from Stonehenge. (The sarsen stones, meanwhile, were likely found 20 or 30 miles away from the monument.) As for how the bluestones made that long journey, we only have theories: Some scholars believe they were dragged on wooden rafts, although others have suggested that a glacier carried the stones at least part of the way. Most archaeologists scoff at the glacier theory, however, and research in 2019 at outcroppings in the Preseli Hills both conclusively linked them to Stonehenge and confirmed evidence of quarrying work around 3000 BCE — the same era when Neolithic builders were first constructing the mysterious stone circles. That means human hands took the rock from the locations in Wales, but as for exactly how, we simply don’t know — and possibly never will.

The Oldest Example of Knitted Socks Comes From Ancient Egypt

Around 300 CE, in the Roman Egyptian city of Antinoöpolis, a child stuffed their feet into a pair of striped wool socks. The child’s name has long been lost to history, but one of the socks is now likely the oldest piece of knitted footwear ever discovered. Pulled from a 1,700-year-old refuse heap during a British excavation in Egypt in 1913–14, the socks now live at the British Museum in London. In 2018, they underwent multispectral imaging that revealed they were once as colorful as some of the cotton creations that adorn our feet today. Scientists found tiny traces of three plant-based dyes (red, blue, and yellow) that ancient Egyptians used on the wool to create seven beautiful shades of stripes. The Egyptians also used a single-needle looping technique, now called “nålbinding,” to create the socks. The technique predates both modern knitting and crocheting, and is named for the many ancient examples that have been found in modern Norway.

Today, some consider pairing socks with sandals a fashion faux pas, but ancient cultures around the Mediterranean felt differently. These particular Egyptian socks had two compartments for toes, and were specifically designed to fit sandals by separating the big toe from its companions. Centuries earlier, ancient Greeks wore socks made from animal pelts along with their sandals. Turns out, pairing socks and Birkenstocks may be one of humanity’s oldest footwear traditions.

Ancient Greek and Roman Sculptures Were Originally Painted

Sculpture from classical antiquity is often presented in museums, textbooks, and more as a world of white marble. But these representations aren’t an accurate portrayal of the past: Ancient Athens and Rome were full of eye-popping color, with statues sporting vibrant togas and subtle skin tones. In fact, no sculpture was considered complete without a dazzling coat of paint.

Over time, these impermanent paints — left unprotected from the elements — wore away, leaving behind unblemished stone and a false legacy of monotone marble. This perception of the “whiteness” of antiquity was cemented in the 18th century, tied to racist ideals that equated the paleness of the body with beauty. When German scholar Johann Winckelmann (sometimes called the “father of art history”) glimpsed flecks of color on artifacts found near the ancient Roman cities of Pompeii and Herculaneum, he brushed off the work as Etruscan — a civilization he considered beneath the grandeur of ancient Rome. Besides bits of color still clinging to some statues, other evidence of the Mediterranean’s colorful past survives in frescoes from Pompeii (which even depict a Roman in the act of painting a statue). In recent decades, the art world has been busy recreating the colorful past of Western civilization as archaeologists use UV light to illuminate certain pigments and art exhibits travel the world to unshroud the colorful palette of these ancient civilizations.

France Has One of the World’s Largest Collections of Standing Stones

The Carnac Stones are a group of more than 3,000 megalithic standing stones in the French village of Carnac, Brittany. These stones date back to the Neolithic period and were probably erected between 3300 and 4500 BCE. They are one of the world’s largest collections of menhirs — upright stones arranged by humans. There is no real evidence to confirm their purpose, but that hasn’t stopped researchers from hazarding guesses. Some theorize they were used as calendars and observatories by farmers and priests. According to Christian mythology, the stones are pagan soldiers who were petrified by Pope Cornelius. Local folklore, meanwhile, says that the stones stand in straight lines because they were once part of a Roman army. The story goes on to say that the Arthurian wizard Merlin turned the Romans to stone.

Not All Vikings Came From Scandinavia

Sweden, Norway, and Denmark receive most of the attention regarding Viking history, but a group of warriors known as the Oeselians lived on a large island called Ösel. Known as Saaremaa today, the island is located off Estonia’s coast in the Baltic Sea. According to 13th-century Estonian documents, Oeselians built merchant ships and warships that could carry about 30 men each.

In 2008, workers inadvertently discovered a burial ground in the town of Salme that included human remains, along with swords, spears, knives, axes, and other weapons. Archaeologists excavated the site (and later a second site nearby) and found the remains of two Swedish ships dating to about 750 CE. One ship contained neatly ordered remains and the other more haphazard, indicating battles had taken place. Archaeologists believe the two ships likely carried Swedish Vikings who met their end while attacking the Oeselians.

The Americas Contain More Pyramids Than the Rest of the World Combined

In ancient Mesoamerica, a region spanning from much of modern-day Mexico through most of Central America, peoples such as the Inca, Aztec, Maya, and Olmec had their own styles of pyramids dating back to about 1000 BCE — and they built a lot of them. Unlike Egypt, they weren’t used exclusively for tombs.

The most well-known Mesoamerican pyramids are the ones in Teotihuacan, an Aztec city near present-day Mexico City. The Pyramid of the Sun, the largest of the structures, and the nearby Pyramid of the Moon were both constructed by putting rubble inside a set of retaining walls, building adobe brick around it, then casing in limestone. The Pyramid of the Sun hides an extra secret: another pyramid, accessible through a cave underneath. These pyramids were built between 1 and 200 CE, although the pyramid inside the cave is even older.

The Great Pyramid in La Venta, an ancient Olmec civilization by present-day Tabasco, Mexico, is much different: It’s essentially a mountain made of clay. Later Olmec pyramids were also earth mounds, only faced with stone in a stepped structure.

The largest pyramid on the planet by volume, not height, is the Great Pyramid of Cholula, or Tlachihualtepetl, in Mexico. It dates back to around 200 BCE, and is essentially six pyramids on top of one another. Later civilizations expanded on previous construction, taking care to preserve the original work. It’s made of adobe bricks and, whether accidentally or through a deliberate effort from the locals, eventually became covered in foliage and was later abandoned. When Spanish invaders led by Hernan Cortez came through, murdered 3,000 people, and destroyed more visible structures, they thought Tlachihualtepetl was part of the natural topography and let it be.

Rome Was the First City in the World to Reach 1 Million Inhabitants

Today, Tokyo is the world’s largest city by population, with more than 37 million residents, but long before the Japanese metropolis took that honor, there was another record-holder: Rome. The ancient city was the world’s largest back in 133 BCE, when it became the first city to reach 1 million inhabitants.

Everyday life in ancient Rome was largely dictated by wealth: Affluent residents lived in finely decorated townhouses (and often had countryside estates for trips out of the city), while lower-income citizens resided in apartment-like buildings called insulae. But all social classes enjoyed the perks of living in a major city, including fresh water piped in from aqueducts, and the availability of markets, entertainment, and even food stalls that served quick meals. Rome’s population eventually declined as the Roman Empire fell, yet no city would surpass its record population for millennia — that is, until London became the world’s largest city, with 1 million people in 1800 and more than 6 million people by 1810.

Egyptian Hieroglyphics Were Undecipherable Until the Rosetta Stone

While digging the foundation for a new fort in July 1799, soldiers in Napoleon’s army found a fragment of stone in the Nile that bore the same message in three languages: Egyptian hieroglyphics, Demotic script, and ancient Greek. By comparing the Greek text to the other two passages, scholars could finally decode the meaning of the hieroglyphics. Before the Rosetta Stone’s discovery, ancient Egyptian writing had been an undecipherable mystery. Later, scholars such as Thomas Young and Jean-François Champollion showed that the hieroglyphics on the stone revealed names of important figures and other details of ancient Egyptian history. Reportedly, Champollion was so excited to have deciphered the mystery that he fainted.

The Incas Used String and Knots to Record Information

Although the Incas had no known written language, they weren’t without a means of recording important information. Quipu were Andean textiles that used a system of colored string and knots to record data. These textiles were both recorded and read by officials known as “quipucamayocs.” Evidence suggests that quipu were first developed by the Wari civilization, who lived in Peru between about 450 and 1000 CE. Scholars believe the Incas used quipu both to record hard data — such as census figures, inventory, and other administrative information — and as a way to encode Incan myths and histories. Because of the Andes’ arid climate, the quipu were well preserved for centuries. Today, hundreds of quipu are displayed in museums around the world, with the biggest collection now residing at the Ethnological Museum of Berlin in Germany.

The Great Pyramids of Giza Created Whole Cities Around Them

Building pyramids as large as the Great Pyramids of Giza was a major undertaking, and required a lot of labor — especially the Great Pyramid of Khufu, which, at 481 feet high, was the tallest building in the world for thousands of years. (The date of its construction is debated, but may have begun around 2550 BCE.)

Archaeologists have uncovered two “towns” around the Great Pyramids that housed not only pyramid-builders, but bakers, carpenters, weavers, stoneworkers, and others who supported day-to-day life. Some lived in family dwellings with their own courtyards and kitchens, while others, likely itinerant workers, slept in something more like a barracks. There is so much we don’t know about these areas, but one thing’s for sure: Based on animal bones and pottery found around the site, everyone there was very well fed… and had plenty of beer to drink.

The Tale of Genji — Often Considered the World’s First Novel — Ends Inconclusively

Spread across 54 chapters and some 1,300 pages (in English), Murasaki Shikibu’s Genji Monogatari, or “The Tale of Genji,” explores the tumultuous love life of its aristocratic titular hero during Heian-period Japan (794–1185 CE). Written around the beginning of the 11th century, Genji is an incredibly ambitious work featuring some 400+ named characters and a 70-year-long narrative that spans generations. Because of its realistic setting, psychological depth, and the detailed development of its heroes — Prince Genji and his son Kaoru — many consider Genji to be the world’s first novel, and thus Shikibu, who served as a lady-in-waiting at Japan’s imperial court, the world’s first novelist. An instant success, the book is still hugely influential in Japan today.

But one detail about the story has perplexed readers and scholars for a millennium: The ending isn’t much of an ending. One of Kaoru’s love interests becomes a Buddhist nun, and Kaoru is foiled in an attempt to make contact with her — hardly a satisfying conclusion after 1,000+ pages of Heian-era court romance. Translators have debated whether this abrupt and unsatisfying ending was the author’s intention or if the story remains incomplete, perhaps because Murasaki died before she could finish it. Others argue that she might not have had a concept of a traditional narrative ending, and anyway was not writing for publication. Instead, Genji’s many chapters were originally passed among the women of court in handwritten notebooks. Scholars will likely never know the definitive answers behind the ending, but the abruptness gives Genji a modern feel and reinforces the novel’s pervading Buddhistic sense of “mono no aware,” a phrase associated with the “beautiful yet tragic fleetingness of life.”

Latvian Vikings Were Known as the “Last Pagans”

A tribe of fierce Viking warriors known as the Curonians lived along the Baltic coastline of modern-day Latvia starting around the fifth century CE. The Curonians were referred to as Europe’s last pagans, since they resisted all attempts to convert to Christianity long after neighboring nations did so — by some accounts, they practiced ancient rituals into the 19th century. They frequently raided Swedish settlements and attacked merchant ships, often forming alliances with other groups.

The Curonians were also among the region’s wealthiest groups, primarily due to the trade of amber (precious fossilized tree resin). The Baltic region contains vast amounts of amber, nicknamed “the gold of the North,” and Baltic amber was once traded all over Europe and northern Africa. One of the Curonians’ primary settlements, Seeburg, was along the Baltic coast in modern-day Grobina. There, you can visit the Curonian Viking Settlement, an attraction that immerses visitors in folklore and activities such as archery, boat trips, and excursions to visit historical sites.

Rome Still Uses an Aqueduct Built During the Roman Empire

While the Romans didn’t invent the aqueduct — primitive irrigation systems can be found in Egyptian, Assyrian, and Babylonian history — Roman architects perfected the idea. In 312 BCE, the famed Roman leader Appius Claudius Caecus erected the first aqueduct, the Aqua Appia, which brought water to the growing population of the Roman Republic. Today, the Acqua Vergine — first built during the reign of Emperor Augustus in 19 BCE as the Aqua Virgo — still supplies Rome with water more than 2,000 years after its construction (though it’s been through several restorations).

The main reason for the aqueduct’s longevity, along with that of many of Rome’s ancient buildings, is its near-miraculous recipe for concrete. An analysis by the Massachusetts Institute of Technology discovered that Roman concrete could essentially self-heal due to its lime clasts (small mineral chunks) and a process known as “hot mixing” (mixing in the lime at extremely high temperatures). Today, researchers are studying how the material functioned in the hopes of applying secrets from the Eternal City to today’s building materials.

Featured image credit: Original photo by David Madison via Getty Images