How South Korea Built a 21-Mile Wall in the Ocean

South Korea took on the impossible: building the world’s longest seawall directly into the open ocean. Stretching 33.9 km (21 miles) across the Yellow Sea, the Saemangeum Seawall reclaimed 400 square kilometers of new land and broke a world record held by the Dutch since 1932. Here is the complete engineering breakdown of how engineers dumped 60 million tonnes of granite into deep coastal currents, survived 3 direct typhoon strikes, and sealed an ocean bay that had been tidal for 10,000 years. 📌 What You’ll Discover in This Video: • How 60 million tonnes of rock were placed in turbulent ocean currents • The installation of 480-tonne steel sluice gates in 50 km/h winds • Why Dutch hydraulic engineering expertise was brought in to seal the final 300-meter gap • How engineers paved a 33 km high-speed coastal highway across the crest • The transformation of 401 km² of reclaimed seabed into modern industrial territory 🔔 Subscribe to NextGen Manufacturing for in-depth engineering breakdowns and megaproject documentaries! #SaemangeumSeawall #Megaprojects #Engineering #Construction #SouthKorea #Infrastructure ⚠️ IMPORTANT: ABOUT THIS VIDEO ------------------------------------------------------------------- This is an educational documentary analyzing the engineering and construction of public infrastructure, based entirely on open-source information. All visuals and animations are 100% synthetic, AI-generated conceptual representations. No real footage of the construction sites or personnel was used. This video is purely informational and intended for educational purposes only. Music from #InAudio: https://inaudio.org/ Track Name. Giants League Timestamps: 0:00 - The Impossible Highway Built on the Sea 2:12 - Battling Tides Faster Than Olympic Swimmers 5:28 - The Secret to Closing a Massive Bay 8:03 - From Toxic Swamp to Industrial Hub 12:10 - The Unexpected Consequences of the Wall