It's a day of celebration for workers building Four World Trade Center.
More than a thousand workers will be in attendance as the final beam will be placed on top of the 977-foot skyscraper.
Developer Larry Silverstein will also be on hand.
Before it's raised, the beam will be signed by some of the workers.
"This building is basically like a butterfly just released from the cocoon right now displaying its beautiful colors and the shape and size of this building here. It's a big day for the boys and girls here at tower 4," said Tishman Construction Superintendent Frank Hussey.
Four World Trade is slated to open in the fall of 2013.
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