Spanish architect Santiago Calatrava, designer of the station, said the Oculus resembles a bird being released from a child's hand. The roof was originally designed to mechanically open to increase light and ventilation to the enclosed space. Herbert Muschamp, architecture critic of The New York Times, compared the design to the Bethesda Terrace and Fountainin Central Park. Cost and delays[edit] The Transportation Hub has been dubbed "the world's most expensive transportation hub" due to its massive cost for reconstruction—$3.74 billion dollars.[38][44] By contrast, the proposed two-mile PATH extension connecting Newark Liberty International Airport to the NWK-WTC service is projected to cost $1.5 billion.[45] The hub has also been criticized for being delayed almost 10 years.[46] Originally, the reconstruction was to be funded by the Federal Transit Administration, which gave approximately $1.9 billion to the project. The costs of the hub were still expensive, but it was to be finished at budget in 2009. In 2014 dollars, the cost of the hub and the adjacent Fulton Center, combined, was $5.1 billion.[47] The hub cost twice as much in 2014 as it should have originally cost in 2004.[46] A single hallway in the elegantly constructed hub cost $225 million and was billed as the "world's most expensive hallway",[48] while construction, maintenance, and management alone cost $635 million; the Port Authority awarded several subcontracts, most of them costly.[46] In addition, over $500 million in cost savings was overlooked.[46] The price of the station was further driven up by Calatrava's architectural decisions.[a 1] He wanted to import custom-made steel from a northern Italian factory, which cost $474 million, and have a columnless, aesthetically based design; skylights in the ground, instead of trees;[a 2] and large, soaring "wings", or rafters.[46] Another $335 million was added to the cost overrun because the Port Authority of New York and New Jersey had to build around the New York City Subway's IRT Broadway – Seventh Avenue Line (carrying the 1 train), since the Metropolitan Transportation Authorityrefused to close the line due to fears of inconveniencing commuters from Staten Island taking the Staten Island Ferry. The line had to be supported on a bridge over the station instead of on columns through the station.[46] In 2012, Hurricane Sandy damaged several hundred million dollars worth of materials.[46] The hub's skyrocketing costs also attracted much controversy, with an editor at The New York Times saying that "Mr. Calatrava is amassing an unusually long list of projects marred by cost overruns, delays and litigation", referring to his other projects around the world that were over budget.[49] Especially because the current station has a ridership of only 46,000 daily passengers compared to 250,000 at Grand Central Terminal) some think that the renovation is overpriced and overstylized.[46] On November 5, 2015, the opening was delayed to early 2016, due to a leaking roof.[50] The director of the Port Authority, Pat Foye, declined to hold an event to celebrate the opening of the Hub, describing it as "symbol of excess" and noting he was "troubled with the huge cost" of the construction project.[51]

The National September 11 Memorial & Museum (known separately as the 9/11 Memorial and 9/11 Memorial Museum) are the principal memorial and museum, respectively. They commemorate the September 11, 2001 attacks, which killed 2,977 victims, and the World Trade Center bombing of 1993, which killed six.[4] The memorial is located at the World Trade Center site, the former location of the Twin Towers, which were destroyed during the September 11 attacks. It is operated by a non-profit corporation whose mission is to raise funds for, program, own, and operate the memorial and museum at the World Trade Center site. A memorial was planned in the immediate aftermath of the attacks and destruction of the World Trade Center for the victims including those involved in rescue operations.[5] The winner of the World Trade Center Site Memorial Competition was Israeli architect Michael Arad of Handel Architects, a New York- and San Francisco-based firm. Arad worked with landscape-architecture firm Peter Walker and Partners on the design, a forest of trees with two square pools in the center where the Twin Towers stood.[6] In August 2006, the World Trade Center Memorial Foundation and the Port Authority of New York and New Jersey began heavy construction on the memorial and museum.[7] The design is consistent with the original Daniel Libeskind master plan, which called for the memorial to be 30 feet (9.1 m) below street level—originally 70 feet (21 m)—in a plaza, and was the only finalist to disregard Libeskind's requirement that the buildings overhang the footprints of the Twin Towers. The World Trade Center Memorial Foundation was renamed the National September 11 Memorial & Museum in 2007.[8] On September 11, 2011, a dedication ceremony commemorating the tenth anniversary of the attacks was held at the memorial. It opened to the public the following day; the museum was dedicated on May 15, 2014 and opened on May 21. Three months after its opening, the memorial had been visited by over a million people.[9] In 2012 the 9/11 Tribute Center collaborated with the 9/11 Memorial to offer private tours, which are hosted by family members of victims, first responders, and survivors.