隨著戰爭結束，音樂在M段再度回到祥和的氣氛，讚頌宏偉的工程。鐵路運輸的發達促進了滇越周邊的發展，呈現欣欣向榮之景，最後以恢弘的氣勢結束。In the foggy morning, a steam train slowly drove along the iron bridge and the steep mountain wall, and the music began with a slow atmosphere. As the train moves forward, the whole song tells the story of the construction of the Yunnan-Vietnam Railway in flashback. After the gentle music ended, the atmosphere suddenly became strange, describing the scene of workers working in a dangerous environment, sometimes accompanied by explosives and construction sounds, showing the difficulty of building railways in the past.
With the development of the music, Section D came to the Allegro. The composer used compact and fast sound groups, as well as triplets and quintuplets one after another, to create a sense of tension in transporting materials when every second counts. In the context full of speed, the percussion and brass instruments are used to simulate the sound of railway level crossings, and the saxophone solo phrases are added, as if you are in the fire of war.
With the end of the war, the music returned to a peaceful atmosphere in the M section, praising the magnificent project. The development of railway transportation has promoted the development of the surrounding areas of Yunnan and Vietnam, showing a thriving scene, and finally ended with a magnificent momentum.