In a twist on the Tao tenet of emptiness, New York City is a place where empty space can be worth more than anything that one might fill it with—so goes the real estate industry in our fair city. Yet overdevelopment is all the more reason for urbanites to appreciate negative space as respite from the never-ending crowds. Whether or not you dwell in a concrete jungle, it's a pleasant surprise to have the chance to appreciate a bustling neighborhood's negative architectural space in from an unexpected perspective.

New York City-based artist Peter Wegner took to the urban streets and turned the city's famed cityscape upside down to unveil his own natural—and otherwise invisible—inverted constructions.

Wegner's series of "Buildings Made of Sky" diptychs are constantly changing shape based on the revival and construction of the buildings around them. Depending on the hour, you can catch them afire with the reds and pinks of a sunset or the elegant blue of nighttime—especially during the biannual phenomenon known as Manhattanhenge. Arbitrary though their boundaries may be, the stratospheric skyscrapers read as clear as day.

Since we don't recommend trying to capture this view firsthand in the middle of Midtown—Manhattan's merciless sidewalks are no place for public handstands—you can view more of Wegner's invisible city on his website.

For good measure:

Via Design Taxi