“…Among the various types of relics, salt‐manufactured relics are important material evidence showing the historical development of salt production necessary for human life. Archaeological studies of salt production history began with the discovery of salt production relics in Europe, and intense studies were conducted in European countries including Romania, Bulgaria, Austria, Germany, Spain, Great Britain and France (Brigand et al, 2013; Fielding & Fielding, 2006; Zant, 2016). Thereafter, in North‐East Asia including China, a number of salt production sites have been discovered, and areal salt production history has subsequently become an interesting field of archeological study (Flad et al, 2009; Sun, 2008; Zhu et al, 2005).…”