Chashan was originally named Dongshan. It was a treasured place with good geomantic omen and caught the fancy of the Queen Mother of the West. The Queen Mother of the West sent the mountain god, who transformed into a Taoist priest, to build a temple here, which is now the former site of the Prajna Temple. She also planted three tea seedlings beside the "Number One Scholar Well". Nourished by the essence of heaven and earth and the spring water of Chashan, the tea seedlings grew thick branches and lush leaves.

They were several times taller than ordinary tea trees, and their trunks were so thick that several people could barely encircle them. The shade of the tea trees covered dozens of mu of land, which was a great wonder in the world. The fragrance of the tea leaves was very rich, and the brook water in Chashan was clear, cool and sweet. The tea leaves flowed down along the stream, spreading their fragrance far and wide. Those who smelled the fragrance enjoyed good health, and those who drank the tea water had sharp ears and clear eyes. Therefore, it was highly praised near and far and had an excellent reputation. As a result, Dongshan was renamed "Chashan".