The process of boring has been completed for the longest section of tunnels of Dali-Ruili railway, marking an important milestone in the construction of the railway that connects Dali Bai Autonomous Prefecture with Ruili City in southwest China's Yunnan Province. It took six years of arduous work in complex geological conditions to complete the tunnels that connect Pupiao Town in southern Yunnan with the eastern bank of the Nujiang River. The 330-kilometer railway is a key section of the China-Myanmar international railway corridor.