The Sanxingdui Site is an ancient Shu culture site dating back approximately 5000 to 3000 years, during the late Neolithic period. In January 1998, it was announced by the State Council as a "National Key Cultural Relics Protection Unit" and has now been included in the list of World Cultural Heritage Key Protection Units. At the Sanxingdui site, many bronze human masks were unearthed, totaling more than 20 earth human masks, divided into three types: large, medium, and small. These bronze mask groups, represented by the vertical eye masks, are one of the most distinctive and spiritually cultural relics in Sanxingdui. They are the earliest and largest mask groups unearthed in China.