Sichuan basin was called Bashu in ancient times. What is the geographical relationship between Na Ba and Shu?

These are the names of two ancient countries, which are used to refer to two different areas in the basin caused by topography. Ba refers to eastern Sichuan, such as Chongqing. Located in the east, it also includes the Three Gorges area in the west of Hubei Province. Most of the terrain is hilly, and because of mountainous, humid climate, cloudy and foggy, Chongqing is also known as the "foggy city". So the hot pot in Chongqing is hotter than that in Chengdu. In agriculture, the proportion of planting and fishing is equal. Shu refers to the western part of the basin, such as Chengdu. Covering most of the basin. The terrain is mostly plain, and the land of abundance refers to Chengdu Plain. Agriculture is dominated by planting, supplemented by aquaculture.