The concert and congress building De Doelen exists out of three complexes, that can be used separately from each other. Each part has its own entrance, a big hall and several foyers with service-spaces. Following a series of urban-design studies centered on the Weena thoroughfare and the Kruisplein, Jan Hoogstad was asked, in the early 1990s, by De Doelen concert and congress building (1966) to research the potential for a future extension. This research resulted in a masterplan that provided for a reduction in size of the Karel Doormanstraat, thereby creating a new building site alongside the Kruisplein. This is were some years later the new college for music and dance (Codarts) was realised. A spacious roof terrace has been created between the existing large hall and the new foyers. Through an air-bridge the congress center is connected to the five-star hotel The Westin next door.