Ikoma Tunnel, Kyoto, Japan

In 1911, Obayashi-gumi signed a contract with Osaka Electric Railway Co. (now Kintetsu Railway Co., Ltd.) to construct a tunnel through the Ikoma mountain range which separates Osaka and Nara prefectures. This tunnel had a total length of 3,388 metres, making it the longest double-track tunnel in Japan at the time. The project presented enormous challenges to the engineers, including soft ground, spurting groundwater and, in 1913, a devastating cave-in.

The tunnel was completed in 1914 after three years of construction utilising forcibly laboured Koreans working in horrid conditions. Locked inside the tunnel many of them died of hunger and diseases. 

There are 4 major recorded disasters since Ikoma Tunnel construction started

1. In 1913, 152 people were buried alive when part of the tunnel collapsed. Nara built a monument outside the tunnel to comfort the dead

2. In 1946, a massive train car fire in the tunnel that left 23 people dead and another 75 people injured.

3. In 1948, an express train picked up speed down an incline in the Ikoma tunnel. The 21 year old train driver tried to slow the speeding train down, but the brakes failed. It collided with a local train ahead and the effects were devastating. 49 people lost their lives and 282 people were injured.

4. In 2005, a tragic train derailment at Amagasaki, claimed the lives of 107 people. 

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