1,600-Year Old Demon-Slaying Mega Sword Unearthed in Japan

A massive seven-foot-long iron sword has been found in a burial mound alongside other archaeological treasures from hundreds of years ago.

The huge sword, known as a dakō sword, was found in the city of Nara in Japan last November. It had a wavy, snake-like shape, and is thought to have been meant to be used to protect the dead from evil spirits.

The sword was buried along with a two-foot-wide, one-foot-tall shield-shaped mirror weighing 124 pounds, thought to be a daryu mirror, which were also used to ward away evil spirits. The combination of these items may indicate that the individual they were alongside was important in military and ritualistic matters, Nara University archaeology professor Naohiro Toyoshima told Japanese Kyodo News.

"[These swords] are prestigious objects of high society," archaeologist and ancient Japanese sword expert Stefan Maeder told LiveScience.

These relics were found during excavations in the Tomio Maruyama burial mound, thought to have been built in the 4th century during the Kofun period, which lasted from A.D. 300 to 710. The site is Japan's largest circular burial mound, measuring 357 feet in diameter.

The blade is about 2.3 inches wide, but the partially remaining scabbard is about 3.5 inches wide due to the meandering shape, said the researchers in a statement from the Nara board of education and the city's archeological institute. "It is also the largest iron sword in Japan and the oldest example of a meandering sword."

The mirror is the first of its kind to have been unearthed, but the massive sword is one of around 80 similar relics to have been discovered across Japan. The sword is, however, the largest specimen of its type, and is twice as large as the second-largest sword found in the country. Larger swords with the distinctive wavy shape of dakō swords are thought to have greater powers to protect against evil spirits, ArtNews reported, with the sword being so large that it was likely not meant for combat against people.

"(These discoveries) indicate that the technology of the Kofun period (300-710 AD) are beyond what had been imagined, and they are masterpieces in metalwork from that period," Kosaku Okabayashi, the deputy director for Nara Prefecture's Archaeological Institute of Kashihara, told Kyodo News.

These burial mounds, known as "kofun" after the Kofun period during which they were built, are found across Nara and the rest of Japan. According to LiveScience, there may be up to 160,000 of the mounds.

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