The one-billion-cubic-meter underground natural gas reservoir was a result of partnership between China and Turkey, and a project undertaken by contractor China Tianchen Engineering Corporation. It was Turkey’s first salt cavern gas storage project, as well as the world's largest single-cavity salt cavern gas storage at present.?In general, work was carried out to pump down fresh water through the borehole in order to dissolve the salt bed. Then the brine was extracted to form a cavity. At last, natural gas was injected into the cavity and the remaining brine was squeezed out.