The basic trend of the Silk Road was formed in the Han Dynasty around AD. It starts from Chang 'an (Jin 'an), the capital of the Western Han Dynasty, or Luoyang, the capital of the Eastern Han Dynasty, passes through Longxi or Guyuan westbound to Jincheng (now Lanzhou), then passes through Wuwei, Zhangye, Jiuquan and Dunhuang counties in the Hexi Corridor, exits Yumenguan or Yangguan, and passes through Bailongdui to Loulan, Lop Nur. In the Han Dynasty, the Western Regions were divided into South Road and North Road, and the two roads diverged in Loulan. To the north, it passes through Quli (now Korla), Qiuci (now Kuqa) and Gu Mo (now Aksu) to Shule (now Kashgar). South Road starts from Shanshan (now Ruoqiang) and passes through Qiemo, Jingjue (now Minfeng Niya Site), Khotan (now Hotan), Pishan and shache to Shule. From Shule to the west, across Congling (now Pamir) to Dawan (now Fergana). From here, we can go west to Daxia (now Afghanistan), Sogdian (now Uzbekistan), Rest in Peace (now Iran), and as far as the plowshare in Daqin (the eastern part of the Roman Empire) (also known as Li Xuan, in Alexandria, Egypt). The other road runs from the southwest of Pishan, crossing the crossing (now Darier, Pakistan), passing through Cobin (now Kabul, Afghanistan) and Wuyishan (now Sistan), and heading southwest to Tiaozhi (now the head of Persian Gulf). If you go south from Bin to India (now Karachi, Pakistan), you can also reach Persia and Rome by sea. This is the basic trunk line of the Silk Road formed after Zhang Qian made two missions to the Western Regions in the period of Emperor Wu of the Han Dynasty. In other words, the narrow Silk Road refers to the above-mentioned roads.

The Silk Road in history is not static. With the change of geographical environment and the evolution of political and religious situation, some new roads are constantly opened up, and some roads have changed or even been abandoned. For example, Bailongdui between Dunhuang and Lop Nur is a Ya Dan terrain, which often disorients travelers. In the early Eastern Han Dynasty, the northern Xiongnu on the Mongolian plateau was defeated and forced to move westward. After the Central Plains dynasty firmly occupied Yiwu (now Hami), it opened up a "new road to the north" from Dunhuang to Yiwu. From Yiwu via Gaochang (now Turpan) and Yanqi to Qiuci, it meets the former Silk Road North Road. During the Southern and Northern Dynasties, the north and the south of China were antagonistic, and the east and the west in the north were also harmonious. Under such circumstances, the exchanges between the Southern Dynasties, Song Dynasty, Qi Dynasty, Liang Dynasty and Chen Dynasty and the Western Regions were mostly along the Yangtze River to Yizhou (now Chengdu), then to Longhe (now Songpan) in the north, passing through Tuguhun Capital on the shore of Qinghai Lake, passing through Qaidam Basin to Dunhuang in the west, and meeting with the main road of the Silk Road. Or cross the Altun Mountain Pass to the west, enter the Shanshan area of the Western Region, and meet with Silu South Road. This road is called "Tugu Hundao" or "Henan Road", and today people also call it "Qinghai Road". From the Central Plains or the north of Hexi Corridor to the Mongolian Plateau, then to the northern foot of Tianshan Mountain in the west, across the Ili River to the broken leaves (near tokmak today), and into Central Asia. This road was later called "Beixin Road", which was very prosperous during the Mongol Khanate and the Yuan Dynasty.

Apart from the Silk Road on land, from the Han Dynasty, China people opened a waterway from Guangdong to India. After the Song Dynasty, with the further development of southern China and the shift of the economic center of gravity to the south, the sea routes from Guangzhou, Quanzhou, Hangzhou and other places have become increasingly developed, going further and further, from Nanyang to the Arabian Sea, and even as far as the east coast of Africa. People call these maritime trade routes "Maritime Silk Road".