Three Gorges primarily famous for its scenery, the Three Gorges region is also historically and culturally important in China. Many settlements and archaeological sites are in danger of being submerged by the rising reservoir of the Three Gorges Dam. Due to the lithological conditions of its different regions, the valleys of the Three Gorges are narrow in some areas and broad in others. Most narrow valleys occur in regions where there is limestone, which is relatively hard and resists erosion. However, water can flow along deep vertical fractures, eroding underneath. As the limestone bed is gradually undercut, parts of it fall into
Three Gorges of Hubei Province (), in the middle of Xiling Gorge. On May 20, 2006, the reservoir dam was completed, and the water level quickly reached the initial level of above the downstream river. The project was completed by the end of 2008, with a ship lift completed in 2015. The dam and Three Gorges Reservoir has had a massive impact on the region's ecology and people, involving the mass relocation of towns and villages. The higher water level has changed the scenery of the Three Gorges so that the river is wider and the mountains appear lower. However, the mountains