Railway network is a railway network system composed of interconnected railway trunk lines, branch lines, tie lines and railway hubs. At present, China has formed a railway network skeleton with Beijing as the center and provincial capital cities as the center, connecting many railway hubs of different sizes, and the hubs have become the main trunk lines of China's railway network skeleton:

1: north-south transportation hub: Beijing-Guangzhou line

From Beijing south to Shijiazhuang, Zhengzhou, Wuhan and Changsha to Guangzhou, the southern gate of the motherland. Along the way, it runs through six provinces and cities, crosses five major river basins, passes through the North China Plain, the Two Lakes Plain and the hilly areas in the south of the Yangtze River, crosses the Nanling Mountains and connects the Pearl River Delta. It is densely populated, rich in products, developed in economy, densely populated in towns and very busy in traffic. The goods shipped to the south mainly include coal, steel, wood and export materials, while the goods shipped to the north mainly include rice, non-ferrous metals and imported materials.

2. East-west coastal traffic artery: Beijing-Shanghai line

The Beijing-Shanghai line starts from Beijing, passes through Tianjin, Jinan, Xuzhou and Nanjing, and reaches Shanghai, the largest city in China. It runs through Beijing, Tianjin and Shanghai and Hebei, Shandong, Jiangsu and Anhui provinces, crosses four major water systems and connects North China Plain, Jianghuai Plain and Yangtze River Delta. Beijing-Shanghai line connects Beijing-Shenyang line in the north and Shanghai-Hangzhou line in the south. The Beijing-Shanghai line is an important industrial and agricultural production base in China with low terrain, dense population, numerous towns, rich coal resources and developed economy. The goods shipped to the south are mainly coal, steel, wood and cotton. The goods shipped to the north mainly include machinery, instruments and department stores.

3. The second largest transportation center running through the north and south: Beitongpu-Taijiao-Liu Jiao.

The whole line starts from Datong, Shanxi, passes through Taiyuan, Jiaozuo and Zhicheng, and reaches Liuzhou. Basically parallel to the Beijing-Guangzhou line. Along the line, it passes through five provinces (regions), spans three major river basins, and runs through the Loess Plateau, the mountainous areas of western Henan, Jianghan Plain, the mountainous areas of western Hunan and the hills of Guangdong and Guangxi. With a total length of 2395KM, it is rich in agricultural and sideline products such as grain, cotton, oil and tobacco, and minerals such as coal and non-ferrous metals. This line plays an important role in perfecting the railway layout in China, improving the capacity of coal transportation in Shanxi and diverting the traffic between Beijing and Guangzhou.

4. Beijing-Kowloon Line, the third largest transportation hub running through the north and south.

The Beijing-Kowloon Line starts from Beijing and passes through Tianjin, Hebei, Shandong, Henan, Anhui, Hubei, Jiangxi and Guangdong to Kowloon, Hong Kong. It has a total length of 2538KM, spanning five major water systems, namely Haihe River, Yellow River, Huaihe River, Yangtze River and Pearl River, and running through North China Plain, Poyang Lake Plain, Dabie Mountain, Jinggangshan and Guangdong and Guangxi hills. The area along the line is not only an important producing area of agricultural and sideline products such as grain, cotton and oil in China, but also an area rich in mineral resources and tourism resources. This route plays an important role in promoting economic development along the route and maintaining Hong Kong's long-term stability and prosperity.

5. The south-north trunk line running through the southwest: Baocheng-Chengkun line.

It starts from Baoji in the north, crosses the Qinling Mountains and Daba Mountain, crosses the western Sichuan Plain, flies over the Minjiang River, crosses the Jinsha River and reaches Kunming, with a total length of 1754KM. There are many mountains, rapids and dangerous beaches along the way, as well as many "underground railways and air stations". The total length of bridges and tunnels in chengdu-kunming railway accounts for 40% of the total length of the line, and the engineering difficulty is rare in the history of railway construction in the world. This line is connected with Baoji Longhai Line and Chengyu Line. Along the line is China's multi-ethnic settlements, rich in specialty products, mineral resources and forest resources. The completion of the railway has promoted the economic construction in the southwest and strengthened national unity, and it is also an important channel connecting the northwest.

6. The artery crossing the Central Plains and Northwest China: Longhai-Lanxin Line.

Lianyungang starts from the Yellow Sea in the east, passes through Zhengzhou, Xi and Lanzhou, reaches Urumqi, passes through six provinces and regions, crosses Huanghuai Plain, Yuzhong Plain, Guanzhong Plain, Loess Plateau, Hexi Corridor and Turpan Basin, and crosses Tianshan Mountains to the north of Xinjiang, with a total length of 3652KM. It is the longest railway trunk line in China, passing through several ancient capitals and famous historical and cultural cities in China, and is rich in coal, oil, cotton, storage products and other minerals along the line. The construction of this railway is of great significance for communicating the economic ties between the economically developed eastern region and the developing northwest region, promoting the economic and tourism development in the western region and consolidating the border defense. In addition, the westbound railway can go directly to the Baltic coast and Atlantic coast through Central Asia, becoming the most important "Eurasian Continental Bridge" in the world, and also a shortcut for China to Central Asia, the Middle East and Europe. The completion of this continental bridge will play an important role in developing China's foreign trade and speeding up the opening up along the border.

7. Beijing-Baotou-Baolan Line

The Beijing-Baotou line runs from Beijing westbound via Hohhot to Baotou, with a total length of 833KM, and the Baolan line runs from Baotou westbound via Yinchuan to Lanzhou, with a total length of 980KM. The line starts from Beijing in the east, crosses the mountainous area in northern Hebei, crosses Zhangbei Plateau and Inner Mongolia Plateau, crosses Hetao Plain and Ningxia Plain to Lanzhou, connects six provinces (cities, districts) and communicates with North China and Northwest China. There are abundant resources such as coal, iron, pond salt and phosphate rock along the line, as well as important animal husbandry bases and commodity grain bases in China. The goods shipped to the west mainly include steel, machinery and wood. The goods shipped to the east are mainly coal, ore and livestock products. This line is of great significance for promoting the economic ties between North China and Northwest China, sharing the transportation pressure of the Longhai Line, building ethnic minority areas and consolidating border defense.

8. East-west trunk line across Jiangnan: Shanghai-Hangzhou-Zhejiang-Jiangxi-Hunan-Guizhou-Kunming line.

The whole line starts from Shanghai in the east, passes through six provinces and cities such as Zhejiang, Jiangxi, Hunan, Guizhou and Yunnan, and connects the Yangtze River Delta, Jiangnan hills and Yunnan-Guizhou Plateau, with a total length of 2677KM. It is the east-west artery that runs across the south of the Yangtze River. The eastern section of the line is densely populated, with developed industry and agriculture, and the western section is rich in coal, iron and other resources. The goods shipped to the east mainly include grain, timber and non-ferrous metals, while the goods shipped to the west mainly include steel, machinery, cement and daily necessities. This is a railway trunk line that is parallel to the Longhai Line and the Yangtze River Line and closely connects the east and the west, which is of great significance to speeding up the economic construction of Jiangxi, Hunan, Guizhou and Yunnan.

9. Northeast Railway Network's self-provided trunk lines: Harbin-Dalian and Binzhou-Suibin lines.

The northeast railway network is centered on Harbin and Shenyang, and connected by Harbin-Dalian and Binzhou-Suibin lines, forming a "D"-shaped skeleton, connecting more than 70 trunk lines and branch lines in the whole region, which is unique and self-contained. The Harbin-Dalian line starts from Harbin in the north and passes through Changchun, Shenyang and Anshan to Dalian, with a total length of 944KM. The Harbin-Dalian line connects the major industrial centers, political centers and the largest seaport in the three northeastern provinces, passing through important agricultural areas and densely populated areas. It is one of the trunk lines with the strongest transport capacity and the largest passenger and freight volume in China, and has become the pillar of economic development in Northeast China. Binzhou-Suibin line starts from Manzhouli in the west and passes through Harbin to Suifenhe, with a total length of 1483KM. Both ends are connected with the Russian railway, which is an important international railway line with rich specialties along the way. It is the supply base of timber, grain and livestock products in China, and also the origin of oil, coal and timber.

10: trunk lines connecting the inside and outside of the customs: Beijing-Shenyang line and Beijing-Nantong line.

The Beijing-Shenyang line starts from Beijing in the south, passes through Tianjin and Qinhuangdao, passes through Shanhaiguan and reaches Shenyang along the Liaoxi Corridor, with a total length of 850KM. Along the way, it is an important city in China, and also an area where coal, steel, machinery, oil and other production bases are concentrated. It is one of the railway trunk lines with the highest passenger and freight density in China. It is also the most important channel to contact inside and outside the customs.

The Jingtong line is 870 kilometers long, from Changping, a suburb of Beijing, to Chifeng, Inner Mongolia, and then to Tongliao. It is an important railway for Shanxi's coal clearance and timber transportation in Northeast China, and the second railway trunk line connecting North China and Northeast China, which is of great significance to reducing the transportation pressure of Beijing-Shenyang line and the economic development of eastern Inner Mongolia.