Yanglou Cave has Guanyin Spring, Shiren Spring, and Liangyin Spring, all of which flow through the town like rivers. At that time, many tea houses represented by "Jushengchuan" and "Sanyuchuan" were located here. In order to highlight the importance of water and imply the prosperity of business, the word "chuan" was pressed on top of brick tea and sold to herdsmen in the border areas. When herdsmen purchase brick tea on the market, they only recognize the "Chuan" brand tea and only buy it without hesitation when they touch the "Three Bars" with their hands: the "Chuan" brand trademark has been recognized by the state as a "Chinese time-honored brand".