Summary of How the world's longest underwater tunnel was built - Alex Gendler

00:00:00 - 00:05:00

The video discusses the construction of the world's longest underwater tunnel, which is located beneath the Strait of Gibraltar and was completed in 2016. The tunnel was designed to improve trade and transportation between Europe and Africa, and has been used by over 20 million passengers each year. However, because of the Channel Tunnel's historical connection to refugees trying to enter Britain illegally, it has also become a site of conflict.

• 00:00:00 The Channel Tunnel is a tunnel that links England and France and is the longest underwater tunnel in the world. It was made possible by the invention of the tunnel boring machine and the discovery of a stable layer of chalk marl below the seabed. The project's most urgent obstacles were ones no engineer could solve, such as water seeping into the rock and cracks in the chalk layer. However, with careful planning and use of a variety of tools, the tunnel was completed in 1994. Since then, it has been a major transportation link between the two countries, with over 20 million passengers using it each year. However, because of the Channel Tunnel's historical connection to refugees trying to enter Britain illegally, it has also become a site of conflict.
• 00:05:00 Alex Gendler discusses the construction of the world's longest underwater tunnel, which was completed in 2016. The tunnel is located beneath the Strait of Gibraltar, and was designed to improve trade and transportation between Europe and Africa.