Around the end of the 18th and at the beginning of the 19th century, Xieng Khouang was the center of a kingdom of the Hmong (Meo). In 1832, it was conquered by the Vietnamese, who annexed the region.
The town of Xieng Khouang was totally destroyed during the Vietnam War. Even though it has been rebuilt in 1975, the name Xieng Khouang is now primarily used in reference to the province of the same name.
The provincial capital is Muang Kham. The most important place near the Plain of Jars is Phonsavan with a small airport serving the region.
The Plain of Jars is roughly 10 kilometers southeast of Phonsavan, at about 1,000 meters above sea level. Scattered over the plain are hundreds of enormous clay jars, each about 1 to 2.5 meters high, with a diameter of about 1 meter.
Scientists have yet to find an explanation as to how the clay jars found their way onto the plain, or what purpose they may have served. Archaeologists have come up with some creative theories, including claims declaring them brewery cauldrons. More likely, the jars were enormous urns.
Many jars have been destroyed or damaged during the Vietnam War, when American planes bombed positions of the communist Pathet Lao.