This morning, crews officially placed the final pieces of the spire atop 1 World Trade Center—making the building the tallest in New York City (and the United States) at 1,776 feet.

Last week, on the second anniversary of Osama bin Laden's death, the 408-foot spire was lifted from the ground to the top of 1 WTC. Weather had prevented it from being permanently installed until today.

Steven Plate, who is overseeing WTC construction, told MyFoxNY, "It will give a tremendous indication to people around the entire region, and the world, that we're back and better than ever."

While the Port Authority insists that the spire part of the building, some building experts say that if it's only an antenna, then it's not truly 1776 feet tall. (A previous design had the spire encased in cladding, which made it less antenna-y and more building-y, but it was scrapped due to cost.)

Future tenants in the building, which is slated to open next year, are include the federal General Services Administration, Chinese firm Vantone, and Conde Nast (whose employees aren't thrilled about it). There will also be an observatory with stunning views.