Many cities have a set of "twin towers." These in Amsterdam are exceptional because unlike others that simply soar into the sky, these also impose an uneasy sense of balance on the viewer. They're only 64 meters tall, but use their textured white surfaces to stand out from their surroundings. In what is becoming more and more common in European architecture, these buildings play a trick on the mind and appear to have a displaced center of gravity. Creative use of crevices and setbacks make the windowed offices appear to hinge on a pair of obelisks that our mind assumes are too insubstantial to support such a weight. Of course, physics and the whims of creative architects dictate differently, otherwise these twins would fall into each other.

Photograph courtesy of Patrick Buijs.