Cranes install base of spire on roof of 1 WTC
The first piece of the spire for One World Trade Center is lowered by construction cranes into position on the roof of the tower, Tuesday, Jan. 15, 2013 in New York. When the spire is completed the building will top off at 1776 feet (541 meters), making it the tallest building in North America. (AP Photo/Mark Lennihan)