Archaeologists found evidence for salt boiling industry in form of several features at a site in Huanghua, Hebei province, China. The sites date to the Tang Dynasty (618—907 AD).
The state of preservation of archaeological features at these sites vary, as the majority of the sites is intact, but some are reported to have been damaged. The size of the archaeological features is said to range range from 1 to 6 meters in diameter. There are also a number of ash ditches and holes reported to have been found around the salt-boiling areas. The site has been dated to the Tang Dynasty times basing on the finds of porcelain shards and bricks.
(after People’s Daily Online)