There is a boulder on the northeast bank of Wanshi Lake, which is engraved with the word “Suoyun” broadwise, which was inscribed by Yao Yingfeng, the coastal defense commander of Xiamen in the thirty-seventh year during the reign of Emperor Kangxi in the Qing Dynasty. Legend has it that this place was where Zheng Chenggong trapped and killed Zheng Lian in the same year. In the late Ming and early Qing dynasties, Zheng Lian, the elder brother of Zheng Chenggong under the same great-great-grandfather, was granted the title Marquis Dingyuan and stationed at Wanshi Rock of Xiamen for his meritorious service in entering Fujian with the King of Lu, the regent at that time. In the Mid-Autumn Festival in August of the seventh year in Shunzhi period in the Qing Dynasty, Zheng Chenggong maneuvered to trap and kill Zheng Lian here in the name of joining forces, and merged its navy, clearing obstacles on the road for establishing a base to resist Qing and recover Taiwan in Xiamen. This site is a municipal cultural relic protection unit.