Four walls of water cascaded into the East River off Manhattan when they were unveiled in a public art spectacle that Mayor Michael Bloomberg called the "most unexpected'' waterfalls between North America and Africa. More InformationPhotos by Mark Mason
A Great Challenge
"It's been quite a journey. It's been a great challenge to achieve this,'' artist Olafur Eliasson said, describing many middle-of-the-night tests to pump water over the metal scaffolding.
