Our proposal for the GITC proposes a linear system of lightwells/greenhouses along the axis of Yeongdongdaero aiming to bring daylight and vegetation deep into the underground levels of the new transport facility. The lightwells are shaped as a family of horizontal arches to enable various vertical environmental flows of daylight, ventilation and a vegetated atmosphere in the underground while maintaining the structural integrity of the slabs. The lightwells will act as natural ventilation engines, able to regulate air movement to respond optimally to seasonal climatic variations.

Systematic air-quality planting on the edges of the lightwells will couple daylight and vegetation in the formation of an underground park which explores an intricate, cavernous space as an expression of its underground monumentality. Cascades of vertical circulation systems will descend from the ground level to the deepest levels of the underground transport facilities, flooded with daylight and vegetation.

The interface between the GITC and the public ground level, we have located an arena—shaped plaza, which is warped into auditorium-shaped stands on the North and South ends in order to introduce a theatrical quality to the urban space, while momentarily bracketing the flow of pedestrians flooding the space from the adjacent COEX and GBC complexes to produce a sense of a collective urban space. The Seoul Arena would frame the entrance into the underground facilities while providing an ideal space for urban performances which are already well established in Yeongdongdaero, for the space to become an enclave for global cultural exchange in Seoul.

On the Samseong side, the auditorium floor folds onto itself to shield the audiences or the visitors from sun and rain, doubling as an acoustic reflector in the case of placing a stage underneath. On the Bongeunsa side, we propose a vegetated auditorium for a more relaxed and casual audience, aiming to connect to the natural character of Bongeunsa Park. The lifting of the N/S ends of the Arena will produce an optimal microclimate for the space, shielded from acoustic intrusion, air pollution and wind.