Aqua Tower

Jeanne Gang designed Aqua in 2009 by giving every floor a differently shaped concrete balcony, so the tower reads as rippling water from a distance. The shapes are not only sculpture: they are calculated to shade the glass, break the wind that torments tall Chicago buildings, and interrupt the flight lines that kill migrating birds against downtown towers. At 82 stories it was, on completion, the tallest building in the world designed by a woman-led firm. Neighbors on the same floor can see each other across the curves, which residents say makes it the rare high-rise where people actually meet.