Before railway transportation became the main mode of transportation, the geographical location of Yibin was much more important than that of Mianyang. In the era of handicraft industry such as wine making and paper making, Yibin's industry is more developed than Mianyang's; With the opening of baoji-chengdu railway, the layout of the third-line construction and the arrival of several historical opportunities, Mianyang has surpassed Yibin, Nanchong, Luzhou, Neijiang, Zigong and other old industrial cities and regional economic centers in Sichuan. The advantages of Mianyang are: Mianyang is closer to Chengdu and more convenient to go out of Sichuan; Chengdu-Mianyang first line is the most active area in Sichuan economy; Mianyang's industrial doors are complete and similar to Yibin; Mianyang enjoys more preferential policies given by the state; Mianyang has more national defense research institutes than Yibin; There are more universities in Mianyang than in Yibin. Mianyang's climate is cooler than Yibin's, and Mianyang society pays more attention to education and personnel training.