A truck runs at the construction site of the Yellow River tunnel on Huanggang Road in Jinan, east China's Shandong Province, June 22, 2025. The excavation work of the Yellow River section of the Huanggang Road Yellow River tunnel was completed on Sunday, marking a breakthrough in the construction of the tunnel project.

The 5,755-meter-long tunnel, with 3,290 meters excavated by a 17.5-meter diameter TBM, is the largest underwater TBM tunnel currently under construction in the world. (Xinhua/Xu Suhui)

Staff workers work at the construction site of the Yellow River tunnel on Huanggang Road in Jinan, east China's Shandong Province, June 22, 2025. The excavation work of the Yellow River section of the Huanggang Road Yellow River tunnel was completed on Sunday, marking a breakthrough in the construction of the tunnel project.

The 5,755-meter-long tunnel, with 3,290 meters excavated by a 17.5-meter diameter TBM, is the largest underwater TBM tunnel currently under construction in the world. (Xinhua/Xu Suhui)

Staff workers are pictured at the construction site of the Yellow River tunnel on Huanggang Road in Jinan, east China's Shandong Province, June 22, 2025. The excavation work of the Yellow River section of the Huanggang Road Yellow River tunnel was completed on Sunday, marking a breakthrough in the construction of the tunnel project.

The 5,755-meter-long tunnel, with 3,290 meters excavated by a 17.5-meter diameter TBM, is the largest underwater TBM tunnel currently under construction in the world. (Xinhua/Xu Suhui)

Staff workers work at the construction site of the Yellow River tunnel on Huanggang Road in Jinan, east China's Shandong Province, June 22, 2025. The excavation work of the Yellow River section of the Huanggang Road Yellow River tunnel was completed on Sunday, marking a breakthrough in the construction of the tunnel project.

The 5,755-meter-long tunnel, with 3,290 meters excavated by a 17.5-meter diameter TBM, is the largest underwater TBM tunnel currently under construction in the world. (Xinhua/Xu Suhui)

A tunnel boring machine (TBM) works at the construction site of the Yellow River tunnel on Huanggang Road in Jinan, east China's Shandong Province, June 22, 2025. The excavation work of the Yellow River section of the Huanggang Road Yellow River tunnel was completed on Sunday, marking a breakthrough in the construction of the tunnel project.

The 5,755-meter-long tunnel, with 3,290 meters excavated by a 17.5-meter diameter TBM, is the largest underwater TBM tunnel currently under construction in the world. (Xinhua/Xu Suhui)

Staff workers work at the construction site of the Yellow River tunnel on Huanggang Road in Jinan, east China's Shandong Province, June 22, 2025. The excavation work of the Yellow River section of the Huanggang Road Yellow River tunnel was completed on Sunday, marking a breakthrough in the construction of the tunnel project.

The 5,755-meter-long tunnel, with 3,290 meters excavated by a 17.5-meter diameter TBM, is the largest underwater TBM tunnel currently under construction in the world. (Xinhua/Xu Suhui)