China Build a Tunnel Under the Sea So Long Even Americans Can't Believe It

China wants to dig a tunnel under the sea so long that nothing on Earth comes close. 🌊🚄 Between the cities of Dalian and Yantai lies the Bohai Strait. The two cities are barely 100 km apart, yet the trip between them can take up to 8 hours by ferry or road. China's answer is a proposed 123 km (76-mile) undersea rail tunnel, with around 90 km running beneath the sea. High-speed trains would cross it at 250 km/h and cut the journey to just 40 minutes. ⏱️ That would make it almost four times longer underwater than the current world record, Japan's Seikan Tunnel. 🇯🇵 It would also have to pass through one of the most earthquake-prone regions in China. ⚠️ In this documentary, we explore: 🌊 Why two neighboring cities are separated by a sea 📜 The 30-year-old dream that keeps coming back 📏 How it compares to the Channel Tunnel and the Seikan Tunnel 🌋 The fault line hidden beneath the Bohai Sea 🛠️ How engineers could dig 90 km under the ocean 🇨🇳 The undersea tunnels China has already built 💰 The cost, the risks, and whether it will ever happen Do you think China will actually build it? Tell us in the comments! 👇 📍 And let us know where in the world you're watching from. 🔔 Subscribe to Hidden World Docs for more documentaries on the world's most extraordinary megaprojects. ━━━━━━━━━━━━━━━━━━━━ ⚠️ DISCLAIMER 🎬 Some visuals in this video are AI-generated or digitally created for illustration and storytelling. They may not show the actual locations, structures, or events exactly as they are. 🚧 The Bohai Strait Tunnel is a proposed project. As of 2026, it is in the research and planning stage and is not yet under construction. Figures such as length, speed, cost, and timeline come from publicly available reports and may change as planning continues. 📚 This video is made for educational and informational purposes only. We aim for accuracy, but we recommend checking official sources for the latest updates. ━━━━━━━━━━━━━━━━━━━━ #China #Megaprojects #Engineering Music From #InAudio: https://inaudio.org/ Name:- Farewell https://youtu.be/EDhT27YbyqI?si=mIoUR-TmyzlEba6-