The main goal of our Station 20 project is to bring natural light into the subterranean levels of the subway station. Given the north-south orientation of the station, we have decided to create glazed slits in the sidewalks which allow direct sunlight to reach the passengers waiting for the trains at the platforms. The entrances on terrain level are marked by two green-walled boxes levitating 2,30m from the ground and are situated symmetrically on the opposite sides of the street. The entrances are equally easily accessible from both sides of the neighborhood and lead through a two-flight stair to the level of the cashier’s desk. The middle level of the station, which can also be used as an underpass, distributes the passengers into two directions – to the Sofia city centre and to the Sofia airport. A single-flight stair and an escalator lead to the subway level, while there is a separate escalator for the arrived passengers. The whole platform is top-lit while only the passageways at mid-level for arriving and departing passengers perforate the sky light.