Baskunchak

Lake Baskunchak is a salt lake of 115 km² in Astrakhan Oblast, Russia, located at 48°10′N 46°53′E, about 270 km north of the Caspian Sea, and 53 km east of the Volga. Since 1997 the area is protected as part of the Bogdinsko-Baskunchakski Nature Reserve.

The surface elevation of the lake is 21 m below sea level. It is fed by a river that draws from an area of 11,000 km². The salinity of the lake is about 300 g/l. Since the 8th century its salt was mined and traded along the Silk Road. Nowadays the lake's salt of distinct purity covers 80% of Russia's salt production. Depending on demand, 1.5 million to 5 million tons of salt are mined per year.

Source: Wikipedia