The Port Authority announced that Calatrava's design, which had yet to be referred to as the Oculus, would be an "enduring monument" to those who lost their lives on 9/11. "It will be a lamp of hope in the middle of Lower Manhattan, creating an unbroken line of natural light from the platforms to the sky," Calatrava said at the time.

At the time, the project was estimated to cost $2.21 billion and to open in 2009.

At the ceremony commemorating the start of construction on the site, Calatrava and his daughter release doves as a symbol of "rebirth" for the Lower Manhattan development.

Four years after the design for the Oculus was unveiled, the first pieces of its steel arches are placed on-site.

Calatrava's original design called for the wings to open and close, much like the architect's design for the Quadracci Pavilion at the Milwaukee Art Museum. Alas, it was not to be: Budget cutbacks forced the Port Authority to keep the hub's from moving, though the glass skylight at its top is retractable.

In the New York Times, David W. Dunlap writes that "The public centerpiece of the project, an aboveground entrance at Church Street known as the Oculus, has taken on its finished oval shape. The sweeping ceiling beams of the mezzanine are in place."

The hallway, which also features Calatrava's ribbed design (akin to the belly of a whale, or some other animal-skeleton metaphor), connects the World Financial Center (now Brookfield Place) to One World Trade Center and the PATH station.

The first of the new PATH platforms opens, with a mosaic called "Iridescent Lighting" along one of its walls.

The final steel rafter of the Oculus is put in place, giving Calatrava's structure the full effect of looking like a bird in flight. (Or a kitsch stegosaurus—your call.)

A scathing piece in the New York Times details many of the problems that led to the transit center's many delays and cost overruns, including a sped-up timeframe, Calatrava's need for steel, and (shocker) George Pataki and Michael Bloomberg's hubris.

It's a nickname that's sure to stick for some time. The magazine's Calatrava profile yields other gems, such as this quote: "'He's one of the great designers,' says Mitchell Moss, director of NYU's Rudin Center for Transportation. 'But this is a fucking train to Jersey.'"

In November of 2015, it's reported that construction around 3 World Trade Center is causing leaks into the transit hub, pushing the opening date back yet again to the first half of 2016.

Port Authority announces that the WTC hub and Calatrava's Oculus are set to open in March 2016. But the Westfield mall that will occupy the hub still doesn't have a firm opening date—"August" is the closest to a confirmed date that's been given thus far.

After more than a decade and $4 billion, Calatrava's transit hub (and the Oculus) are due to (finally) open to the public, though there still many parts that are still off-limits.