Neijiang, a county in the Eastern Han Dynasty, was once named Han 'an and Zhongjiang. The northern part of the Tuojiang River is called Niuchushui, which is the Beijiang River. The southern section is Zhijiang, called Nanjiang, and this is Zhongjiang. At the beginning of Sui Dynasty, it was changed to Neijiang to avoid the taboo of Taizu Yang Zhongzhi. In 1951, it was set as Neijiang City. One said that because of the name of the internal water (that is, the Tuojiang River), the city and county were built on the west bank of the Tuojiang River. At this point, the river meandered into an arc, like a peninsula, and the city was named after it. Neijiang City (also known as Sweet City) is located in the southeast of the land of abundance, on the bank of the beautiful and rich Tuojiang River. Neijiang City is located at the east gate of Sichuan, connecting Chongqing in the east, Chengdu and Ziyang in the west, Zigong, Yibin and Luzhou in the south, Suining and Nanchong in the north, chengdu-chongqing railway and neijiang-kunming railway in the north, and Chengdu, Chongqing, expressway and Neiyi, expressway in the south. The highway density is higher than the national and provincial average, with a mileage of 3,149 kilometers. It is an important intersection of transportation in southeastern Sichuan and even southwestern provinces, with a "central Sichuan hub". It is an important town in eastern Sichuan and one of the eight mega-cities with a population of one million planned and built in Sichuan Province. Geographical location: 114 15 ′-115 26 ′ E and 29 11 ′-31 2 ′ N.. The city covers an area of 5,386 square kilometers and now has jurisdiction over three counties and two districts, namely, Shizhong District, Dongxing District, Weiyuan County, Zizhong County and Longchang County, with 1,111 townships, 2,171 administrative villages, 11 sub-district offices and 253 community residents' committees. At the end of 2118, the total population was 4,251,511, including 841,111 non-agricultural population, 3,411,611 agricultural population and 163,711 hectares of cultivated land, with a per capita arable land area of 1.1385 hectares. Neijiang is located in the center of Sichuan Basin. It is adjacent to Longquan Mountain in the west, and Chongqing is connected with Huaying Mountain in the east. The terrain is gentle, with shallow hills and flat dams alternating, extending to the north and south. Together with the hilly areas of Zigong, Luzhou, Yibin, Deyang, Suining and Nanchong, it constitutes a hilly area in the basin, with a length of 121.5 kilometers from east to west and a width of 94.7 kilometers from north to south. It is a typical landform in the hilly area of central Sichuan. The main landform area is 311-511 meters above sea level. In this landform area, the river network is poorly developed and the soil is insufficient. Neijiang area is a shallow hill in Sichuan basin. The shallow hills, which evolved from the red strata of Jurassic and Baixie, account for 88.8% of the total area, and the rest are low mountains. Longquan Mountain in the northwest and Jiugong Mountain in the southwest are the watershed of Min and Tuo rivers, and the main peaks are 811-1111 meters above sea level. There are the remaining veins of Huaying Mountain in the southeast-Luoguan Mountain and Shengdeng Mountain. The Tuofu watershed in the eastern shallow hills is composed of some ridge-like hilltops, with a general height of 451-561 meters. The whole terrain is high in the northwest and low in the southeast. The highest place in the territory is Lion Rock in Longquan Mountain, with an altitude of 992.3 meters, and the lowest place is at the exit of Shiyang River in Baishui Township, Anyue, with an altitude of 248 meters. There are mountains such as Liamu Mountain and Baiyun Mountain in Neijiang. The city is rich in mineral resources. Energy minerals mainly include coal, natural gas and oil shale; Non-metallic and building materials minerals include limestone, sandstone, shale, refractory clay, bauxite, marble, river sand, gravel and ceramic clay. Metal minerals and scattered elements include iron, potassium and gold, and scattered elements such as aluminum, gallium, rubidium and lithium in salt mines, potassium mines and coal seams; Chemical minerals include salt minerals and potassium-bearing hydromica clay minerals. Neijiang City is located in the center of the basin, with simple geological structure and relatively stable crust. The exposed strata in the area are mainly influenced by three geological structures: Ziwei Dome Anticline, Shengdeng Dome Anticline and Luoguanshan Anticline. The minerals in the city are mainly distributed in Weiyuan, Zizhong and Longchang counties in these three structural belts. Natural gas is mainly produced in two structural belts, Ziwei Dome Anticline and Shengdeng Dome Anticline, with proven reserves of more than 61 billion cubic meters. Gold placer is produced in Zizhong, Shizhong and Dongxing districts along the river bed of Tuojiang River. The mineral resources are mainly coal, natural gas and limestone, and a small amount of salt, potassium-bearing clay, refractory clay, lead soil and gold placer are produced. In the future, the development of mineral resources has great prospects. Neijiang City, influenced by the basin and local natural environment, has the characteristics of mild climate, abundant rainfall, sufficient light and heat and long frost-free period. It is warm in winter and hot in summer, with moderate rainfall. The average temperature is 15℃-28℃, the average temperature in January is 6℃-8℃, and the average temperature in July is 26℃-28℃. The maximum temperature can reach 41℃, the minimum temperature is-5.4℃, and the active accumulated temperature is about 598℃. The territory is rich in heat resources, with the annual average total solar radiation of 89.6 kcal/cm2, the annual total sunshine hours of 1,111-1,311 hours and the frost-free period of 331 days. The number of frosty days in the whole year is generally about 4-8 days, and the disastrous weather is mainly drought, with alternating droughts and floods; In spring, summer, autumn and winter, low temperature, wind and heavy rain occur from time to time, and the rain is remarkable. The annual temperature is obviously dry in winter and dry in spring, at the same time, the phenomenon of summer drought and summer drought also occurs from time to time. The annual rainfall is below 1111 mm, mostly distributed in summer, accounting for about 61% of the annual rainfall. The high temperature period is basically the same as the rainy season, accounting for about 1.7% in spring and only 4% in winter.