The silver spire topping One World Trade Center is fully installed on the building's roof, bringing the structure to its full, symbolic height of 1,776 feet on Friday, May 10, 2013, in New York. The 408-foot spire, weighing 758 tons, will serve as a world-class broadcast antenna. (AP Photo/Mark Lennihan)
The silver spire topping One World Trade Center is fully installed on the building's roof, bringing the structure to its full, symbolic height of 1,776 feet on Friday, May 10, 2013, in New York. The 408-foot spire, weighing 758 tons, will serve as a world-class broadcast antenna. (AP Photo/Mark Lennihan)
A worker holds a guide rope as the final piece of spire is hoisted to the roof of One World Trade Center, Thursday, May 2, 2013 in New York. The piece will be attached to the spire at a later date, capping off the tower at 1,776 feet. (AP Photo/Mark Lennihan)
The final piece of the spire is hoisted to the roof of One World Trade Center, Thursday, May 2, 2013 in New York. The piece will be attached to the spire at a later date, capping off the tower at 1,776 feet. (AP Photo/Mark Lennihan)
The final piece of the spire is hoisted to the roof of One World Trade Center, Thursday, May 2, 2013 in New York. The piece will be attached to the spire at a later date, capping off the tower at 1,776 feet. (AP Photo/Mark Lennihan)
The final piece of the spire is hoisted to the roof of One World Trade Center, Thursday, May 2, 2013 in New York. The piece will be attached to the spire at a later date, capping off the tower at 1,776 feet. (AP Photo/Mark Lennihan)
The final piece of the spire is hoisted to the roof of One World Trade Center, Thursday, May 2, 2013 in New York. The piece will be attached to the spire at a later date, capping off the tower at 1,776 feet. (AP Photo/Mark Lennihan)
The final piece of the spire is hoisted to the roof of One World Trade Center, Thursday, May 2, 2013 in New York. The piece will be attached to the spire at a later date, capping off the tower at 1,776 feet. (AP Photo/Mark Lennihan)
The final piece of the spire is hoisted to the roof of One World Trade Center, Thursday, May 2, 2013 in New York. The piece will be attached to the spire at a later date, capping off the tower at 1,776 feet. (AP Photo/Mark Lennihan)
