In 1970 a kiln site was uncovered during construction work at kilometre 3 on Thadeua Road in Vientiane's Sisatthanak District. Construction was halted only temporarily, and over a one-month period the kiln (known as VS8) was hastily and unprofessionally excavated. More extensive excavations in the surrounding villages were undertaken in 1989 and 1992, uncovering both unglazed and glazed wares and adding to the ever-increasing body of evidence that Laos once had an important ceramic tradition. Of light, translucent green (like celadon) or of various shades of brown, most of the glazed wares took the form of high-quality pipe fragments decorated with simple incisions, stamps and fluting. The kiln itself was of a cross-draft clay-slab type, differing substantially not only from Siamese types but also from all other types in South East Asia. Since that time at least four more kilns have been identified in the area, and surface evidence and topography indicate at least 100 more in the vicinity of Ban Tao Hai and Ban Wat Nak. The area is located close to Vientiane's outer perimeter walls, which have been dated to the 16th century. Radiocarbon dating suggests that the kilns were constructed between the 15th and 17th centuries, and the greater ratio of glazed wares at higher elevations suggests that an increasing number of glazed wares were fired over time. Many of the ceramics unearthed in this area are on display in three unlabelled cabinets in Ho Phra Keo National Museum.