During the Tang and Song Dynasties, two ancient highways were formed in the Sichuan Basin, known as the Northern and Southern Roads respectively. The Southern Road was less prominent. Yet, it was the predecessor of the Eastern Main Road in later times. Against the background that the political and economic center of the Sichuan Basin moved eastward and southward in Ming and Qing Dynasties, Chongqing ascended in importance and could rival Chengdu. The Eastern Main Road gradually took shape and flourished. In the Ming Dynasty, there were 12 post stations along the Eastern Main Road, which were largely inherited in the Qing Dynasty. Along the road were also a large number of shops and posts. The total mileage of the Eastern Main Road was about 1 000 li (500 meters) comprising in total of 10 stages, which would take 11 to 12 days to travel. The western section was often travelled by boat on the Tuojiang River. The Eastern Main Road took shape in the early Ming Dynasty. At the beginning, it was called the “Southeast road”, the “East Road of Sichuan”, or the “East road”. The name “Eastern Main Road” was formed in the late Qing Dynasty and early Republic of China. It has natural and cultural advantages such as connecting Chengdu and Chongqing, low terrain agriculture, abundant water resource, access to the rivers and sea, and close to the salt mines. It was the primary road in the Sichuan Basin and it gave birth to the “Eastern Main Road Economic Belt”. Since the 1990s, the status of “Eastern Main Road Economic Belt” has declined, but the strategy of “Chengdu-Chongqing Double-city Economic Circle” has brought opportunities for the revitalization of the ancient Eastern Main Road.