Developer Larry Silverstein is expected to join construction workers at a ceremony on Monday to mark the milestone for the building at the corner of Liberty and Greenwich streets.
A group of workers are scheduled to sign the beam before it is hoisted to the top of 4 WTC.
Silverstein's company also owns the already completed Seven World Trade Center.
At the anchor building of the site, One World Trade Center, steel has been erected to the 104th floor.
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