Introduction to Taiyi Cave: Three powerful and simple characters "Taiyi Cave" are engraved on the stone wall on the left side of the cave entrance. The calligrapher was Ouyang Xi, a Hanlin scholar in the Qing Dynasty. There are all kinds of strange things in the cave, and there is also Taiyi Zhenren's alchemy pool. Under the pool is unfathomable, with a Yin River and silver-white shrimps that are hundreds of millions of years old.