De Rotterdam is a building on the Wilhelminapier in Rotterdam, designed by the Office for Metropolitan Architecture in 1998. The complex is located between the KPN Tower and Rotterdam Cruise Terminal and was finalized at the end of 2013. On 21 November 2013, the municipality of Rotterdam, as the largest user, received the keys. The design provides space for offices, a hotel and apartments. The 44 floors amount to a total floor space area of about 160,000 m², making it the largest building in the Netherlands. Realisation Construction began in 2009, when the municipality committed itself to hire 25,000 m² of the office space. The highest point (at 149 meters) was reached at the end of 2012, and the building was ready on its scheduled date of 15 November 2013. The total cost at the start of construction in 2009 was estimated to be €340,000,000. Appearance and construction Rem Koolhaas, who once considered a career in film, reasoned that the most frequent view of these structures would be in motion, from the window of a car. As the view changes, the towers, rising from a shared six-story plinth, separate and then merge. The building consists of three interconnected towers that share a thirty feet high base which includes six floors. The lower two layers form a large glass plinth. At about 90 meters above ground the towers – known as West Tower, Mid Tower and East Tower– are shifted a few meters in different directions, which enhances the wind stability and provides space for terraces. In the original design the towers did not touch each other, but in order to simplify the play of forces and to keep the construction affordable they are now connected in a few places. The facade provides the option of natural ventilation. On the west side there are balconies that are accessible from the apartments. Usage De Rotterdam is designed for residency, labor and leisure. The largest part is intended as office space and residency. It has 240 apartments, 72,000 m2 of offices, conference rooms and an underground parking with two floors providing over 684 parking spaces There is also a hotel with 285 rooms and 1500 m2 is assigned to cafes and restaurants. For fitness facilities 2,500 m2 is reserved and for shops 5,000 m2. The functions are grouped into blocks, but the different user groups meet at various places in the building, a