The long-delayed, $4 billion transportation hub is slated to open in 2016. View Full Caption Facebook/WTC Progress

FINANCIAL DISTRICT — The massive, white-winged World Trade Center Oculus is slated to finally open during the first week of March after months of delays, Port Authority sources said.

Earlier this week the Port Authority's program director, Glen Guzi, said during a CB1 meeting that the sprawling centerpiece of the $4 billion WTC transportation hub was set to open "within the second quarter" this year — between April and June.

Port Authority sources said, however, that the timeline for opening is actually earlier. It's now scheduled for the first week of March.

Constructon at the rib-like, Santiago Calatrava-designed Oculus is moving ahead, Guzi said.

The heated, marble flooring in the expansive space has been completed, he said.

The Oculus will be the heart of transportation hub that will connect 10 subway stations and the PATH. The Oculus and the various interconnected concourses that will link the buildings on the World Trade Center site are slated to be lined with storefronts, including an Apple Store, H&M and Eataly.

Rendering courtesy of Port Authority

Once complete, the Oculus will also be used as an event space, likely hosting fashion shows, concerts or food tastings, Guzi said.

Several corridors inside the hub have already opened to the public, including PATH train platforms.