The Great Wall of China is more than twice as long as originally believed, according to the first definitive archaeological survey of the iconic ancient defensive structure.

Released by the State Administration of Cultural Heritage (SACH), the survey began in 2007, mapping every trace of the wall across 15 Chinese provinces.

It emerged that the wall is much longer than previously thought. Indeed, it measures 13,170.6956 miles, or 21,196.18 km. A preliminary study released in 2009 estimated the wall to snake 5,500 miles, or 8,850 km across the country.

A total of 43,721 heritage sites were identified during the survey, "including stretches of the wall, defense works and passes, as well as other related Great Wall facilities and ruins," Tongo Mingkang, SACH deputy chief, said.

Known to the Chinese as the "Long Wall of 10,000 Li", the Great Wall is the world's largest human-made structure -- a series often overlapping fortifications made of stone, bricks and earthen works whose construction begun as early as the 7th century BC.

The defensive structure was first linked up under Emperor Qin Shi Huang in about 220BC. to protect the ancient Chinese empire from marauding tribes from the north.

Since then, many dynasties have maintained and renovated the wall. The majority of the existing structure was reconstructed during the Ming Dynasty (1368-1644).

A warship submerged for two centuries in a river near Washington, D.C., could provide new insight into the relatively obscure War of 1812, say archaeologists who are preparing to excavate the wreck.

The war started because the British, who had been fighting with France since 1803, imposed restrictions on U.S. trade with the French, infuriating Americans. Relations worsened when British ships began intercepting U.S. vessels on the high seas, removing any British-born sailors, and forcing them to serve in the British navy.

The U.S. Congress declared war on the British - including their Canadian colonists - in June 1812.

Archaeologists have unearthed what they believe are the oldest known fish traps that date back to at least 9,000 years.

The remains of seven basket traps were discovered in the Baltic Sea off Sweden by a team of marine archaeologists from Stockholm's Sodertorn University.

The ancient finger-thick hazel rods are thought to be the remains of stationary basket traps, the researchers said.

"This is the world's oldest find when it comes to fishing," Johan Ronnby, a professor in marine archaeology, was quoted as saying by British media.

Arne Sjostrom, a fellow archaeologist who worked on the Sodertorn project, said the sticks seemed to have been used as a "sort of fence to lead the fish into a creel or they were part of the actual creel".

Underneath the thick, virgin rainforest cover in the Mosquitia region of Honduras, archaeologists have discovered ruins they think may be the lost city of Ciudad Blanca. Legends say the "White City" is full of gold, which is why conquistador Hernando Cortes was among the first Ciudad Blanca seekers in the 1500s. But the method the modern researchers used was a little different from previous explorers' techniques. The modern-day researchers flew over the area in a small plane and shot billions of laser pulses at the ground, creating a 3D digital map of the topology underneath the trees.

Archaeologists in London have discovered the remains of an early playhouse used by William Shakespeare's company where Henry V and possibly Romeo and Juliet were first performed.

The Curtain theater, north of the river Thames in Shoreditch, was home to Shakespeare's company - the Lord Chamberlain's Men - before the riverside Globe theater was built.
Remains of walls forming the gallery and the yard within the venue were discovered by archaeologists from Museum of London Archaeology, or MOLA. "This is a fantastic site which gives us unique insight into early Shakespearean theaters," MOLA's Chris Thomas, who is leading the archaeological work, said Wednesday.

The theater was immortalized as "this wooden O" in the prologue of Henry V with the lines: "Can this cock-pit hold within this wooden O, the very caskes that did affright the Ayre at Agincourt?"

Mexican cultural authorities have preserved an archaeological area with several Maya buildings more than 1,500 years old that were buried under a highway in the Yucatan peninsula.

The archaeological zone, comprised of the remains of five Maya buildings, was part of the ancient city of Oxkintok and is located on both sides of the highway, where a roadside stop has been set up so that visitors or travelers can look around, the National Anthropology and History Institute, or INAH, said.

In the ruins of a Buddhist monastery in Afghanistan, archaeologists have uncovered a stone statue that seems to depict the prince Siddhartha before he founded Buddhism.

The stone statue, or stele, was discovered at the Mes Aynak site in a ruined monastery in 2010, but it wasn't until now that it was analyzed and described. Gérard Fussman, a professor at the Collège de France in Paris, details his study in The Early Iconography of Avalokitesvara (Collège de France, 2012).

Standing 11 inches (28 centimeters) high and carved from schist - a stone not found in the area - the stele depicts a prince alongside a monk. Based on a bronze coin found nearby, Fussman estimates the statue dates back at least 1,600 years. Siddhartha lived 25 centuries ago.

The prince is shown sitting on a round wicker stool, his eyes looking down and with his right foot against his left knee. He is "clad in a dhoti (a garment), with a turban, wearing necklaces, earrings and bracelets, sitting under a pipal tree foliage. On the back of the turban, two large rubans [are] flowing from the head to the shoulders," writes Fussman in his new book. "The turban is decorated by a rich front-ornament, without any human figure in it."

The monk stands at the prince's right side, his right forearm shown upright. In his right hand the monk holds a lotus flower or palm (now broken), and in his left is a round object of some kind.

Based on the iconography of the stele, particularly the pipal leaves, Fussman believes the prince is Gautama Siddhartha Sakyamuni, who is said to have achieved enlightenment, become a Buddha - someone of divine wisdom and virtue - and founded the religion of Buddhism. This stele shows him at an early moment in his life, when he has yet to start his fateful journey of enlightenment.

Around 100,000 years ago, the human race was on the brink of extinction. Confined to Africa, our population had fallen to less than 10,000. Yet within a few tens of thousands of years, we began spreading around the world.

New genetic evidence suggests that one factor contributing to the population bottleneck was a massive epidemic of bacterial disease. The bacteria were exploiting two immune system genes, turning them against us. So the solution was simple: get rid of the traitorous genes.

Ajit Varki of the University of California, San Diego and colleagues looked at two genes called Siglec-13 and Siglec-17. Both code for proteins that are involved in controlling the immune system, helping to decide whether immune cells should go on the offensive.

Varki found that both genes are active in chimpanzees, but not in humans. Siglec-13 has been entirely deleted from the human genome, while Siglec-17 is non-functional as a result of losing one letter from its code.

An excavation is underway thanks to the discovery of the bones of a prehistoric mammoth in one Oskaloosa, Iowa, family's backyard.

According to ABC's affiliate ABC5-WOI in Des Moines, the first bones were discovered in July 2010 by a man named John and his two teenage sons when they were walking in the woods of their property looking for blackberries.

One of his sons pointed out what he thought was a ball in the creek below to his family. Once they got closer, John, who has an interest in archeology, noticed a marrow line at the top of the object, said reporter ABC5-WOI reporter Katie Eastman, who interviewed the family.

Realizing this was no ball, the family dug out what has now been identified as a mammoth femur.

Despite discovering the bones nearly two years ago, the bones were brought to the University of Iowa for identification only last month, sparking the interest of Holmes Semken, professor emeritus of Geoscience.

A trove of gold and silver coins and jewelry discovered near the Qiryat Gat in Israel was likely stashed there by a wealthy woman during the Bar Kokhba Revolt, the last Jewish-Roman war, archaeologists announced today (June 5).

Scientists uncovered about 140 gold and silver coins, along with gold jewelry, during an excavation that exposed rooms of a building dating to the Roman and Byzantine period. The treasure trove was wrapped in cloth and hidden in a pit in the building's courtyard.

The jewelry could make even a modern gal smile; among the hoard is a flower-shaped earring and a ring holding a precious stone that is covered with a seal of a winged goddess.

Two sticks of silver in the trove were likely kohl sticks, which were used type of like eyeliner in Arabia and Egypt to darken the edges of eyelids. The coins date to the reigns of emperors Nero, Nerva and Trajan, who ruled the Roman Empire from about A.D. 54 to 117; the emperors' images adorn one side of the coins.

And the other side of the coins shows cultic portrayals of the emperors, symbols of the brotherhood of warriors and mythological gods such as Jupiter seated on a throne or Jupiter grasping a lightning bolt in his hand.