What's the number of the Black Bamboo Club?

The first, eleventh, twenty-first and fourth days of the lunar calendar. According to official website, the government of Heizhu Town, the town holds fairs on the first, eleventh, twenty-first and fourth days of the lunar calendar, so people can buy what they need. Heizhu Town is located in the famous mountain area of Ya 'an City, Sichuan Province, northeast of Baizhang Lake, 26 kilometers away from the famous mountain area. It is the east gate of Ya 'an, bordering Chengdu, Qionglai City and Pujiang County.