Building Rem Koolhaas vertical city, day by day photographs by Ruud Sies De Rotterdam is a unique multifunctional building on the banks of the river De Maas. Covering an area of 160,000 m2 it is a new masterpiece in the oeuvre of architect Rem Koolhaas and his firm OMA and an absolute eye-catcher in Rotterdam. Because of the many functions it can truly be called a 'vertical city'. Photographer Ruud Sies followed the building of the Rotterdam from 2009, when the first shovel went into the ground, until the completion in 2013. The building and construction show the creativity and commitment of many people, revealing a vision for urban life in the 21st century and advances in technology.