An aerial drone photo taken on Aug. 25, 2026 shows vehicles entering a tunnel across the Yellow River in Jinan, east China's Shandong Province. A new tunnel across the Yellow River, China's second-longest river, opened to traffic on Tuesday in Jinan.

Stretching about 5.75 kilometers in total, the tunnel under Huanggang Road features a shield-driven section of roughly 3.3 kilometers, bored by the "Shanhe" shield tunneling machine with a cutting diameter of 17.5 meters, the largest of its kind among underwater shield tunnels in the country. (Xinhua/Zhu Zheng)

A vehicle passes through a tolling station of a tunnel across the Yellow River in Jinan, east China's Shandong Province, Aug. 25, 2026. A new tunnel across the Yellow River, China's second-longest river, opened to traffic on Tuesday in Jinan.

Stretching about 5.75 kilometers in total, the tunnel under Huanggang Road features a shield-driven section of roughly 3.3 kilometers, bored by the "Shanhe" shield tunneling machine with a cutting diameter of 17.5 meters, the largest of its kind among underwater shield tunnels in the country. (Xinhua/Zhu Zheng)

An aerial drone photo taken on Aug. 25, 2026 shows a tunnel across the Yellow River in Jinan, east China's Shandong Province. A new tunnel across the Yellow River, China's second-longest river, opened to traffic on Tuesday in Jinan.

Stretching about 5.75 kilometers in total, the tunnel under Huanggang Road features a shield-driven section of roughly 3.3 kilometers, bored by the "Shanhe" shield tunneling machine with a cutting diameter of 17.5 meters, the largest of its kind among underwater shield tunnels in the country. (Xinhua/Zhu Zheng)

An aerial drone photo taken on Aug. 25, 2026 shows a tunnel across the Yellow River in Jinan, east China's Shandong Province. A new tunnel across the Yellow River, China's second-longest river, opened to traffic on Tuesday in Jinan.

Stretching about 5.75 kilometers in total, the tunnel under Huanggang Road features a shield-driven section of roughly 3.3 kilometers, bored by the "Shanhe" shield tunneling machine with a cutting diameter of 17.5 meters, the largest of its kind among underwater shield tunnels in the country. (Xinhua/Zhu Zheng)

Vehicles run through a tunnel across the Yellow River in Jinan, east China's Shandong Province, Aug. 25, 2026. A new tunnel across the Yellow River, China's second-longest river, opened to traffic on Tuesday in Jinan.

Stretching about 5.75 kilometers in total, the tunnel under Huanggang Road features a shield-driven section of roughly 3.3 kilometers, bored by the "Shanhe" shield tunneling machine with a cutting diameter of 17.5 meters, the largest of its kind among underwater shield tunnels in the country. (Xinhua/Zhu Zheng)

An aerial drone photo taken on Aug. 25, 2026 shows a tunnel across the Yellow River in Jinan, east China's Shandong Province. A new tunnel across the Yellow River, China's second-longest river, opened to traffic on Tuesday in Jinan.

Stretching about 5.75 kilometers in total, the tunnel under Huanggang Road features a shield-driven section of roughly 3.3 kilometers, bored by the "Shanhe" shield tunneling machine with a cutting diameter of 17.5 meters, the largest of its kind among underwater shield tunnels in the country. (Xinhua/Zhu Zheng)