Vast underground transit complex planned for Gangnam

By 2021, Seoul will build a colossal underground transit zone for public transportation that matches the size of the COEX Mall.

Made up of six underground floors, the complex in Gangnam District, southern Seoul, will stretch from Samseong Station on subway line No. 2 to Bongeunsa Station on line No. 9, covering 160,000 square meters (40 acres).

If Seoul manages to connect the complex with COEX Mall and a new shopping mall under construction by Hyundai Motor Group, the three areas will encompass 420,000 square meters in total, or the size of 30 Jamsil Baseball Stadiums.

The sixth underground floor will be 51-meters (167-feet) deep.

City officials laid out the latest urban development plan on Monday, announcing that approximately 1.7 trillion won ($1.5 billion) will be allocated for the project, which is expected to serve some 580,000 commuters daily.

Of the total budget, 506.9 billion won will be funded by the national government, 410.5 billion won by Seoul and the rest by private investment.

Seoul will come up with a master plan by the end of this month, wrap up administrative procedures by the end of this year and open public bidding for an architectural design in early 2017.

The capital is eager to promote the underground zone as a hip transportation hub. It will be serviced by six different rail lines - from subways to KTX bullet trains - and 90 bus routes will pass through the area.

Lee Won-mok, a spokesman from the city’s transportation headquarters, said it will take only five minutes to travel from the new complex to Seoul City Hall, currently a one-hour ride, due to a new high-speed train line.

Several Great Train Express (GTX) lines will pass through the underground transit zone, connecting Seoul with neighboring cities in Gyeonggi. Launched in 2011, the GTX project links Seoul and Gyeonggi with high-speed railways to relieve traffic congestion.

City terminal services for Incheon International Airport, now provided at COEX, will probably be moved to the second basement floor of the new complex. Restaurants and retail will be located on the B-1 floor.

BY YOO SEONG-WOON [lee.sungeun@joongang.co.kr]