According to legend, in ancient times, Baotu Spring flowed fiercely, reaching tens of feet when the spring roared, and many calligraphers' writing tablets were washed away. People and officials in Jinan wanted to invite people with certain official positions and calligraphers to write a monument named Baotu Spring to suppress the surging Baotu Spring, so they chose Hu Maozong, the governor of Shandong Province who worked in Tianshui, Gansu Province.
Hu was good at writing big characters and was a famous calligrapher at that time. He wrote several pictures in succession, and finally chose this one on the tablet, which was carved from fine stones selected by famous masons in Jinan. On the Dragon Boat Festival, Sima Xianning led the officials in the magistrate to erect a stone tablet of Baotu Spring at the source of Baotu Spring. However, it was soon discovered that a "point" symbolizing the cover of Baotu Spring on the stone tablet of Baotu Spring had been washed to Daming Lake by the vacated spring water.
The "Daming Lake" plaque hanging in the south gate of Daming Lake was extended from the Daming Lake Monument in Jiaqing, Qing Dynasty, and was written by Dengzhou people in Jiaqing, Shandong Province. The "Daming Lake" plaque hanging above the southwest gate of Daming Lake was inscribed by Mr. Guo Moruo for Li Qingzhao Memorial Hall in September 1959. Above the east gate of Daming Lake hangs the words "Daming Lake" inscribed by the famous calligrapher Shu Tong in September 1987.