SEOUL-Yongsan Development Co. has completed the schematic design for the $30 billion Yongsan International Business District, planned for a former rail yard maintenance station here. When completed in 2016, the 66-building project will include office, retail, multifamily and hotels, as well as a large park the size of New York City’s Central Park.

The massive 66-building project needed 19 architects to handle all of the concept design, completed in December. Now that the schematic design is done, the detail design has begun, a spokesman for Yongsan tells GlobeSt.com. “Considering the massive scale of the project, it is necessary to schedule the program for design and construction over a number of years,” he says. The groundbreaking for construction will start the first half of 2013, he says.

The four main commercial elements will take up about 37.7 million square feet, with 13.8 million square feet of office, 10.9 million square feet of retail, 10.8 million square feet of multifamily and two million square feet of hotels. Renzo Piano Building Workshop, based in Italy, is designing the tallest structure, a 111-story, five-million-square-foot office tower named Triple One. KPF is designing a 72-story hotel.