Korea's first underground double decker road for light vehicles

In 2007 traffic congestion in Seoul, with its population of 11 million people, was costing the economy approx. USD 7.64 billion. This figure is expected to increase by 5.88% per year in the future. Expansion of road capacity is very urgently needed to address this issue. However, it is difficult to construct roads in the overcrowded city center due to such problems as rapidly increased construction expenses, air pollution and noise problems. Also, the social demand to provide an eco-friendly public transportation system is replacing the existing car-focused traffic system of recent years. Accordingly, it is considered necessary to build tunnels for exclusive use of light vehicles as a way to increase road capacity, provide an expanded green tract of land and improve the air quality of the city.