World Longest Tunnel
The world longest tunnel has been constructed in Switzerland. PC: http://www.gizmag.com/gotthard-base-rail-tunnel-switzerland/43627/ The 57-kilometer long (35-mile long) tunnel connects northern and southern Europe. It took Seventeen (17) years after construction crews started boring beneath the Swiss Alps, the world's longest, deepest tunnel officially opened Wednesday (01 June 2016). It incurs the country $12 billion construction cost PC: http://edition.cnn.com/2016/06/01/europe/switzerland-longest-tunnel-gotthard/ About 2,600 workers have been involved in the construction of the tunnel, with nine losing their lives in the process. For more information please watch this video;