MEGA-PROJECTS

The redevelopment of the World Trade Center is among the most expensive ongoing projects in the world, expected to cost nearly $20 billion by its completion in 2011. A portfolio of photographs taken from three angles above the site shows how, after years of cleanup and delays, the future has begun to take shape. Photographs by Robert Polidori

The eastern half of the site, facing north towards the Church Street post office and the recently rebuilt 7 World Trade Center at left