Rob van Erk
This 20-storey office block stands above the hall of the Exchange by J.F. Staal parallel to Coolsingel. Shaped like a flattened ellipse, it rests on a concrete table held aloft by eight columns, thus minimizing loss of space within the hall below. Its elliptical shape, green glazing and aluminium cladding panels stem from forms and colours in the original building beneath. The WTC proved to be the starting signal for a deluge of high rises in the centre during the 1980s and '90s.