Aerial photo taken on May 31, 2019 shows the Chishui River Bridge of Gulin-Xishui highway under construction on the border between southwest China's Sichuan Province and Guizhou Province. Two sides of the Chishui River Bridge of Gulin-Xishui highway connecting southwest China's Sichuan Province and Guizhou Province across the Chishui River were joined together on Thursday. (Xinhua/Liu Kun)