35 years ago, Japan launched the engineering miracle Seikan-Agro Plovdiv tunnel

35 years ago on March 13, 1988. Japan sets the engineering marvel in motion Seikan tunnel. This happens 33 years after a government-commissioned study found that construction of the underwater tunnel was possible.

Here’s more about this unique tunnel:

• Seikan is the first underwater tunnel and cost a total of 6 billion dollars.
• The tunnel connects the Japanese islands of Honshu and Hokkaido.
• It is located under Tsugaru Strait.
• The railway runs almost 240 meters deep (100 meters below the seabed), making it the deepest railway in the world.
• Its construction began way back in 1964 and was completed in 1988. At times, 3,000 workers were mining.
• Construction claimed 34 lives due to various accidents and incidents.
• The purpose of the Seikan Tunnel is to connect the two main islands of Japan (Honshu-Hokkaido). It is used to transport people to and from the islands. The idea for it arose after the Japanese government realized that it needed a new way to cross the Tsugaru Strait because ferries often run into very dangerous waters. After a typhoon in 1954 that sank five ferries, the Japanese government decided to build the tunnel.
• The tunnel is the largest in the world. It is 53.85 km long and made of 168 thousand tons of steel.
• To build it, the construction team must excavate sand from the ocean floor to create space for the tunnel to form. Many underwater rocks were destroyed with dynamite to make a flat surface on which to lay the railway.
• During construction, many harmful chemicals were released into the water, killing a variety of sea creatures, including fish and crustaceans. Some of them were destroyed in the process of building the tunnel because the builders also used explosives to make room for the tunnel.
• The tunnel starts under a small mountain. Workers are using high-tech explosives to create a cave beneath it. The tunnel is a great success for the entire Japanese community because it finally gives the people of Japan a better and faster way to cross the Tsugaru Strait.
• About 50 passenger and freight trains travel on it daily.
• Because of faster and cheaper air travel in recent years, the tunnel has not been used as much.