Introduction to the first astronomical point in Yunnan: Kunming is one of the ideal locations for actual astronomical measurements in my country. Among the 27 surveying stations in the Yuan Dynasty, there was the Dianchi Lake Surveying Station, which was mapped in the 47th year of Emperor Kangxi’s reign in the Qing Dynasty (1708). ) to 1719, a total of 640 locations in the country and 30 locations in Yunnan were surveyed, but no accurate signs can be found. In the winter of 1934, a retest at Yunnan University was initiated by the Education Department of the Yunnan Provincial Government, the Yunnan Provincial Education Funding Committee, the Yunnan Tongzhi Museum, Yunnan University, and the Kunming Yide Surveying and Mapping Institute, and it was determined that Kunming's position on the earth is 102° east longitude. 41ˊ58.88″, 25°03ˊ21, 29″ north latitude. The monument is engraved in Yunda, so it is called “the first astronomical point in Yunnan”.