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The Plain of Jars

    The Plain of Jars is a collection of large stone jars interspersed throughout the Xieng Khouang plain in the Lao Highlands. The stone structures are mostly made of sedimentary rock and, ranging from 3 to 10 feet high (1 to 3 meters), each can weigh up to 14 tons.

    The Plain of Jars received relatively little Western attention until the 1930s, when French archaeologist Madeleine Colani began surveying the area. Though previous reports of the jars had cited the existence of goods such as carnelian beads, jewelry and axes, the site was mostly looted by the time Colani arrived. Despite this, Colani discovered a nearby cave housing human remains, such as burne bones and ash, leading her to believe that the jars were funeral urns for chieftains. Colani excavated the artifacts, some of which dated to between 500 BC and 800 AD, and published her findings in The Megaliths of Upper Laos.

    Though the Xieng Khouang plain remains the central site of the jars, similar clusters can be connected to form a linear path all the way to northern India. The existence of similar jar clusters in other parts of Asia also led to the belief that the jars were part of a large trade route. Some researchers believe that the jars collected monsoon rainwater for caravan travelers to use during dry season. Travelers would use the water and then leave behind prayer beads or offerings in the jars, thus explaining previous sightings of jewelry and assorted goods.

    Though the caretaker for the Plain of Jars are applying for status as a UNESCO World Heritage site, the area still remains one of the most dangerous archaeological sites in the world. Thousands of unexploded bombs remain from the Secret War of the 1960s, and some of these arms still cause injuries to this day. As such, only Sites 1, 2, 3 and the Quarry are open to visitors, while a number of organizations work to remove explosives and apply for more funding.

Adopted from:  https://www.atlasobscura.com/places/plain-of-jars (October 22,  2018)

Why do researchers believe that Plain of Jars was a trade route?