Walking down the street in New York one day, I glanced up and saw an invisible building suspended between the others. It was upside down, the color of air.

A few steps later, it disappeared. Then, around the next corner, I saw another building like the first. I felt that I had stumbled upon a secret city, luminous and strange.

As I wrote in 2004, when I first began to exhibit this series:

“There are two Manhattans. One is a city of tall buildings; the other is a city of no buildings. This city begins where the architecture leaves off. It’s a city cast in the die of Manhattan, a perfect complement to the built city, a kind of anti-Manhattan. This parallel city has an architecture all its own. It is the architecture of air, the space defined by the edges of everything else, its map redrawn by pigeons and pedestrians, barricades and scaffolding, cranes, trucks, taxis. It’s the city we assume but cannot name. In this city, the buildings are made of sky. It’s the Manhattan that isn’t – without which there could be no Manhattan.”

My project has since grown to include other cities. But the point remains the same, what the poet John Ashbery has called “a nothingness of sky.” If you believe in nothingness, prefer it, the buildings reveal themselves: buildings made of sky.

—Peter Wegner