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The 6 million-ton Great Pyramid of Giza is the last surviving wonder of the ancient world. How did the Egyptians engineer the mighty pharaoh Khufu’s tomb so precisely, with none of today’s surveying and power tools? And who were the thousands of laborers who raised the stones? Were they slaves or volunteers, and how were they housed, fed, and organized? "Decoding the Great Pyramid" presents the latest evidence from groundbreaking archaeological research that has transformed our understanding of the ancient world’s most ambitious engineering project, revealing a “lost city" and intimate details of the lives of the laborers and officials who toiled on the vast construction. Amazingly, French archaeologists recently found the logbook of a labor team that delivered limestone blocks to build the Great Pyramid, yielding crucial insights into the planning and logistics behind the operation. Beyond these construction secrets, "Decoding the Great Pyramid" traces how mobilizing the colossal labor and resources invested in the monument transformed ancient Egypt, uniting a nation behind the common goal of ensuring eternity for the pharaoh and continuing prosperity for everyone in this life and the next. (Premiered February 6, 2019)

New archeological evidence sheds light on the stunning engineering of the Great Pyramid of Giza.

Decoding the Great Pyramid

Canada

US, US Territories, Canada

Explore the intimate connections between the landscape, the colonizing of the continent, and the emergence of our industrial world. Beginning with Native American ancestors who crafted hunting weapons from stone traded across hundreds of miles, the program shows how pre-Columbian civilizations developed an expert knowledge of the landscape and its resources. With the arrival of Europeans, North America’s hidden riches became to key to prosperity, from the gold rush to today’s oil and gas boom. As a result, human activity has transformed the continent on a scale that rivals the geological forces that gave birth to it billions of years before. Yet, scientists warn of sleeping giants like the Cascadia fault, and the earthquake/tsunami one-two punch it could unleash on the Pacific Northwest. Even as we re-mold the continent to suit our needs, geologic processes inexorably continue, and they raise potential risks of catastrophe to our human civilization.

How has the land shaped our lives, from the arrival of the first Americans to today?

Making North America: Human

(This program is no longer available for online streaming.) Our ancient human ancestors once lived only in Africa, in tiny bands of a few thousand hunter-gatherers. Then we moved out of our African cradle, spreading rapidly to every corner of the planet. How did we acquire the skills, technology and talent to thrive in every environment on earth? How did our prehistoric forebears cross the Sahara on foot, survive frigid ice ages, and sail to remote Pacific islands? “Great Human Odyssey” is a spectacular global journey following their footsteps out of Africa along a trail of fresh scientific clues. With unique glimpses of today’s Kalahari hunters, Siberian reindeer herders, and Polynesian navigators, we discover amazing skills that hint at how our ancestors survived and prospered long ago. (Premiered October 5, 2016)

Follow our ancient ancestors’ footsteps out of Africa and into every corner of our planet.

Great Human Odyssey

Ancient Desert Death Trap

Explore mysterious 9,000-year-old Stone Age megastructures found in the Arabian Desert.
Across the Arabian Desert lie colossal, enigmatic structures, some stretching for miles, visible only from the sky. Rediscovered a century ago and once believed to be defensive or ritualistic in nature, new technology is finally uncovering their true purpose and the secrets of the Stone Age people who engineered them. What were these immense, sophisticated constructions used for? Join scientists as they unearth groundbreaking clues, including evidence of a previously unknown culture and their astonishing methods for survival, revealing a monumental story etched into the very stones of the desert. (Premiering October 22 at 9 pm on PBS)

Explore mysterious 9,000-year-old Stone Age megastructures found in the Arabian Desert.

Ancient Builders of the Amazon (Español)

Descubrimientos arqueológicos revelan civilizaciones antiguas olvidadas en la Amazonia.

Ancient Maya Metropolis (Español)

Explora las antiguas ciudades mayas y aprende por qué sus habitantes las abandonaron.

Why Does This Mummy Have So Many Tattoos?

Otzi, a 5,000-year-old mummy, has 61 tattoos arranged in 19 groups across his body.
Researchers used a unique camera sensitive to invisible light to discover the exact number and location of all of Otzi’s tattoos — including a never before seen tattoo on the right side of his chest.
Why Does This Mummy Have So Many Tattoos?Published: July 28, 2025NARRATOR: These are Otzi&#x27;s tattoos. The iceman is the oldest tattooed mummy ever discovered. Researcher Marco Samadelli has been one of Otzi&#x27;s caretakers for nearly 20 years. Recently, Marco set out to inventory every tattoo on Otzi&#x27;s skin.MARCO SAMADELLI: We discovered exactly 61 tattoos.GARY STAAB: That&#x27;s a lot of ink.NARRATOR: Marco&#x27;s research revealed something no one had ever seen before, thanks to a unique camera, sensitive to invisible light.MARCO SAMADLLI: Multispectral imaging is a technique used to see what the eye can&#x27;t see. It&#x27;s with this technique we discovered every single detail, even under the surface of the mummy&#x27;s skin.NARRATOR: The exact number and location of all the tattoos was a mystery until now.MARCO SAMADLLI: We discovered a tattoo that had never been seen before, four parallel lines on the right side of his chest. We were able to see all his tattoos and obtain a complete mapping.AARON DETER-WOLF: 61 tattoos arranged in 19 groups across his body.NARRATOR: Archeologist Aaron Deter-Wolf studies the use of tattoos in ancient cultures.AARON DETER-WOLF: Tattooing has been practiced throughout a huge portion of human history going back at least 16 or 18,000 years before present. During that time period, people have been tattooed for all sorts of different reasons depending on their culture and the region in which they lived. We generally agree that Otzi&#x27;s tattoos don&#x27;t seem on the whole to be decorative or symbolic.NARRATOR: For Aaron and other experts, a key clue to understanding the purpose of the tattoos could be where they&#x27;ve been placed.AARON DETER-WOLF: A number of Otzi&#x27;s tattoos seem to correspond to areas where he suffered from ailments or injuries. He had arthritis in his lower back, and there are tattoos on his lower lumbar area. He had arthritis in his right knee, there are tattoos on the back of his right knee. He had arthritis in his ankles, there are a number of tattoos around both his right and left ankles. Most recently, this new set of tattoos is located on his lower right abdomen. Among the many ailments that he suffered from was gallstones and whipworms in his colon, and this is a place that is very close to those areas and could potentially have been used to treat the pains he was experiencing.NARRATOR: Tattooing the skin to alleviate pain has been the practice of many cultures.AARON DETER-WOLF: And there are therapeutic tattoo traditions that have been documented all across the world, and in India, in Southeast Asia, North America, in the American Arctic.NARRATOR: Otzi&#x27;s tattoos are the earliest direct evidence of this ancient tradition.

Otzi, a 5,000-year-old mummy, has 61 tattoos arranged in 19 groups across his body.

How Harvard Discovered It Has an Original Copy of the Magna Carta

They paid only $27.50 for it from a London bookseller in 1946.
Researchers used ultraviolet scans to compare Harvard Law School’s copy of the Magna Carta, word for word, against the other known originals. Their analysis helped confirm it was an original from 1300.
How Harvard Discovered It Has an Original Copy of the Magna CartaPublished: July 10, 2025NARRATOR: Imagine accidentally encountering an original version of one of the most famous documents in the world, the Magna Carta.DAVID CARPENTER: I thought, &quot;Oh heavens, this looks for all the world like an original of the final 1300 Magna Carta.&quot;NARRATOR: David Carpenter and Nicholas Vincent combed through digital images, including in ultraviolet light, to confirm Harvard Law School&#x27;s copy was actually an original.And in June 2025, they had the opportunity to see the document in person. The researchers discovered just the seventh known copy remaining.Signed in England in 1215, the Magna Carta is the first known document asserting that the king is also subject to the rule of law. It went through six different versions until 1300, the last time it was validated by a king. Back then, scribes wrote over 30 copies to distribute around the country.Harvard Law School paid only $27.50 for it from a London bookseller in 1946.One thing that tipped the researchers off to the document&#x27;s authenticity was the appearance of the handwriting. It was remarkably similar to other confirmed original copies from the same time period, and upon further inspection, they noticed a massive clue, at Westminster in the 28th year of Edward&#x27;s Reign, which puts it at the place and time, 1300, where the other known original copies were signed.NARRATOR: The whole way the first line is written is very comparable in terms of handwriting. So that&#x27;s seen in the other previously known six originals, but also the whole size and shape of the charter.The next step was to match it word for word against the original copies, but there was an issue.DAVID CARPENTER: The key problem was that the lettering, the handwriting in places was faded.NARRATOR: Some of the document&#x27;s text is so faded that it&#x27;s not legible to the naked eye, and in order to confirm its authenticity, the researchers needed to be able to see all of the words.To reveal the faded text, they used different kinds of light, including ultraviolet light and a special camera. Like most documents of its era, the Magna Cartas from 1300 were written on parchment made of animal skin, which contains collagen. When ultraviolet light hits the parchment, it causes the molecules and the collagen to glow.MICHAEL B. TOTH: That ink is almost like a tattoo into that animal skin, and so we would make that animal skin glow, if you will, and backlight that tattoo.NARRATOR: The ultraviolet light also revealed etch marks left in the parchment, even where the ink had faded. These images allowed the researchers to finally confirm the charter&#x27;s authenticity.DAVID CARPENTER: But in the end, I mean it did pass the test with absolutely flying colors and it matches up pretty well exactly with the other six originals. Harvard Law School is one of the great centers of legal studies in the world, and therefore, it&#x27;s very fitting that Harvard Law School should have its own Magna Carta, and I hope it will be inspirational.

They paid only $27.50 for it from a London bookseller in 1946.

What Fish Revealed About This Mysterious Grave

Could these bones be the last remains of a legendary Viking army?
Archaeologists discovered a mass grave of what they thought to be ninth-century Vikings. But for some reason, the radiocarbon dates of their bones, found by measuring a radioactive carbon isotope, appeared much older.
What Fish Revealed About This Mysterious GravePublished: July 8, 2025NARRATOR: This sleepy village in the heart of England was the scene of a gruesome discovery, nearly 300 battle scarred skeletons. Could these be the last remains of a legendary Viking army that swept through medieval Britain? In the 1990, when the archeologists carbon dated those bones, the results were shocking. Many of the bodies appeared to be a century too old to belong to the great Viking Army. A mystery Cat Jarman has been determined to solve.Cat Jarman: Everything that the bones, the artifacts, the coins is really screaming Viking Great Army. But the science, the radiocarbon dates said that&#x27;s not possible.NARRATOR: Scientists date bones by measuring the amount of Carbon-14 they contain. This radioactive isotope remains in the skeleton after death, it decays over time at a steady rate. So by measuring what&#x27;s left in the bones, scientists can figure out roughly when the person died.Cat Jarman: What we didn&#x27;t realize 20 years ago, we actually have to take into account how the carbon that we are dating gets into our bodies. And it actually gets into our bodies through the food that we eat.NARRATOR: It turns out that people with a diet high in fish absorb older carbon than meat-eaters, that&#x27;s because the oceans contain carbon that is 100 of years old. When fish ingest this, and people in turn eat the fish, the ancient carbon enters their bones. Scientists now know that the bones of people who eat fish appear older than they really are, skewing carbon dating results. Cat has also been able to calculate just how much fish each person has eaten by using the distinctive chemical markers seafood leaves in human bones.Cat Jarman: I looked at all these different bones, and it turned out everybody with a sort of wrong date, as it were, had been eating a lot of fish. That was a really brilliant moment actually, to be able to see those dates fitting perfectly. And that meant the entire mass grave could now be dated to the late 9th century, meaning it&#x27;s completely consistent with the Viking Great Army.

Could these bones be the last remains of a legendary Viking army?

A scientist holds up a syringe and a vial

Using DNA to Learn About Rapa Nui Ancestry

Learn how the people of Rapa Nui participated in a genetic study to learn about their ancestors with this video from NOVA: Easter Island Origins.

Topic: Ancient Worlds

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