Answer: China
Notes: China has completed the Tianshan Shengli Tunnel, the world's longest expressway tunnel at 22.13 kilometers. It forms part of the Urumqi-Yuli Expressway, connecting northern Xinjiang to Yuli County, reducing travel time through the Tianshan Mountains from three hours to 20 minutes. The project faced challenges such as high-altitude conditions, complex geology, and environmental concerns near glaciers and water sources. This project supports China’s Belt and Road Initiative, fostering regional economic growth and integration.
