Three Gorges assisted Yu the Great in controling the waters and guiding boatmen. The Xiling Gorge comprises a series of famous gorges, including Military Book and Sword Gorge, Yellow Cow Gorge, and Lantern's Shadow Gorge. In 1919, after Sun Yat-sen had put forward the concept in the Plan for Industrial Development of his (), experts investigated damming the Three Gorges, but it was not until 1994 that the Three Gorges project officially started. In 1944, the Nationalist government recruited John L. Savage, the Chief Engineer of the United States Bureau of Reclamation, who came to China and made a 10-day investigation of
Three Gorges Reservoir Region narrow and where the geography is complex. The mountainous areas represent 74% of the region only with 4.3% plain area in the river valley and 21.7% hilly area. The climate of the reservoir region of the Three Gorges Project is the subtropical monsoon climate. Its location is in the transfer between the northern temperate zone and the subtropical zone, where it is hot and it rains a lot with the annual rainfall of about 1100 mm. The valley of the Three Gorges Reservoir Region below 500 m has an annual temperature 17–19 °C and, with the frost-free period annually lasts