Rebuilding After Terror - A Photo Timeline of Ground Zero

Milestones Toward Rebuilding the Twin Towers

smoldering framework of fallen twin towers
Ground Zero Two Days After World Trade Terror Attack. Chris Hondros/Getty Images (cropped)

After terrorists struck the World Trade Center towers, architects proposed ambitious plans for reconstruction in New York. Some people said the designs were impractical and that America could never recover. Others wanted the twin towers simply rebuilt. Skyscrapers have risen from the ashes and those early dreams have become reality. The architecture at what became known as ground zero is remarkable. Just look at how far we've come and the milestones we've met.

Fall and Winter 2001: Debris Cleared

trucks and loaders under construction lights as debris from the remains of the World Trade Center is lifted from a truck onto a barge
December 2001, Clearing Debris Near Ground Zero. Spencer Platt/Getty Images (cropped)

The terrorist attacks of September 11, 2001 destroyed New York's 16-acre World Trade Center complex and killed an estimated 2,749 people. In the days and weeks after the disaster, rescue workers searched for survivors and then only remains. Many first responders and other workers later became gravely ill with lung conditions brought on by smoke, fumes, and toxic dust.

The collapse of the buildings left some 1.8 billion tons of steel and concrete. For many months, laborers worked through the night to clear away the debris. Barges took the mixture of remains, both human and architectural, to Staten Island. The then-closed Fresh Kills Landfill was used as a sorting ground for evidence and artifacts. "Kill" is a Dutch word meaning small stream and is commonly used throughout American lands first colonized by the Dutch. The New York City Department of Parks and Recreation now controls the area known as Freshkills Park. Artifacts, including saved beams that might be used in the future, were stored in a hangar at Kennedy Airport in Queens.

In November 2001, New York Governor George Pataki and New York City Mayor Rudy Giuliani created the Lower Manhattan Development Corporation (LMDC) to plan the reconstruction of the area and distribute $10 billion in federal reconstruction funds.

May 2002: Last Support Beam Removed

construction site crane with broken beam, workers surrounding it, platforms overlooking ceremony
May 2002, The Last Support Beam Removed From Ground Zero. Spencer Platt/Getty Images (cropped)

The last support beam from the south tower of the former World Trade Center was removed during a ceremony on May 30, 2002. This marked the official end of the World Trade Center recovery operation. The next step was to rebuild a subway tunnel that would extend 70 feet below ground at ground zero. By the one-year anniversary of the September 11 attacks, the World Trade Center reconstruction project was underway.

December 2002: Many Plans Proposed

members of the public scrutinize some of new proposed designs for the rebuilding of New York's World Trade Center
December 2002, Proposed Designs on Public Display. Spencer Platt/Getty Images (cropped)

Proposals for reconstruction of the site stirred heated debate. Emotions remained raw for years after this unthinkable tragedy. How could architecture meet the practical needs of the City and also honor those who were killed in the 9/11 terrorist attacks? More than 2,000 proposals were submitted to New York's Innovative Design Contest. In December 2002, the LMDC announced seven semi-finalists for a master plan to rebuild ground zero. A master plan is an overall concept of an area or architectural space as opposed to the design of a specific building. Typical of architectural competitions, most of the plans presented to the public were never built, because only one could be chosen. All of the proposals were available to the public for review.

February 2003: Master Plan Selected

Architect Daniel Libeskind (L) presents his winning design for the World Trade Center site to New York Governor George Pataki (2nd-L) at a media conference
February 2003, Libeskind Explains His Chosen Master Plan to Government Officials. Mario Tama/Getty Images (cropped)

From the many proposals submitted in 2002, the LMDC selected Studio Libeskind's design, a master plan that would restore the 11 million square feet of office space that had been lost on September 11. Architect Daniel Libeskind proposed a 1,776-foot (541-meter) spindle-shaped tower with room for indoor gardens above the 70th floor. At the center of the World Trade Center complex, a 70-foot pit would expose the concrete foundation walls of the former twin tower buildings.

In a city the size of New York City, underground infrastructure is as extensive as the roots of a tree. This deep basement area is often called a bathtub by engineers. The underground architecture, including the Port Authority Trans-Hudson (PATH) transit system, had to be repaired early on in the rebuilding.

What we see aboveground is the visual treat to what is underneath. In August 2003, Spanish architect and engineer Santiago Calatrava was chosen to design the entrance to a new train and subway station at the World Trade Center site.

2004: Cornerstone Laid and Memorial Design Chosen

white men in suits and red ties unfurl a blue tarp from an engraves pieces of stone that says To honor and remember those who lost their lives on September 11, 2001 and as a tribute to the enduring spirit of Freedom
July 2004, Symbolic Cornerstone Unveiled for 1 World Trade Center. Monika Graff/Getty Images

Daniel Libeskind's design for what was called Freedom Tower, the largest skyscraper in his master plan, was unacceptable to security experts and the developer's business interests. One World Trade Center has a history of redesign. Even before the final design was approved, however, a symbolic cornerstone was laid in a ceremony on July 4, 2004. The new New York City Mayor Michael Bloomberg along with New York State Governor George Pataki and New Jersey Governor James McGreevey unveiled the cornerstone's inscription. Before construction could begin in earnest, architects and planners faced many controversies and obstacles.

At the same time the 1WTC design was being disputed, another design competition was held for a memorial honoring those who died in the terrorist attacks on 9/11 and the twin tower bombing of February 1993.  An astonishing 5,201 proposals from 62 countries were submitted. The winning concept by Michael Arad was announced in January 2004. Arad joined forces with landscape architect Peter Walker to develop the plans. The proposal, Reflecting Absence, has since gone through many revisions.

2005: A Pivotal Year in Rebuilding

barren construction site with skyscrapers and the Hudson River in the background
November 2005, Ground Zero. Mario Tama/Getty Images (cropped)

For more than a year, construction stalled at ground zero. Families of September 11 victims objected to the plans. Cleanup workers reported health problems stemming from toxic dust at ground zero. Many people worried that the soaring Freedom Tower would be vulnerable to another terrorist attack. A top official in charge of the project resigned. What was called "the pit" remained empty to the public. In May 2005 real estate developer Donald Trump proposed simply to rebuild the twin towers and be done with it.

The turning point in all this turmoil came when David Childs, the Skidmore, Owings & Merrill (SOM) architect of Seven World Trade Center, became the lead architect for One World Trade Center. Childs had tried to adapt Libeskind's Freedom Tower, but nobody was satisfied. By June 2005 the tallest skyscraper to be built on the site had been completely redesigned. Architecture critic Ada Louise Huxtable wrote that Daniel Libeskind's vision had been replaced by "an awkwardly torqued hybrid." Nevertheless, David Childs, working for SOM and developer Larry Silverstein, would forever be the design architect of 1WTC.

Work in the pit continued. On September 6, 2005, workers began constructing a $2.21 billion terminal and transportation hub that would link subways to ferries and commuter trains in Lower Manhattan. The architect, Santiago Calatrava, envisioned a glass and steel structure that would suggest a bird in flight. He proposed that each level inside the station be column-free to create an open, bright space. Calatrava's plan was later modified to make the terminal more secure, but the proposed design endured.

2006: Silverstein Takes Control

four older white men standing, smiling in front of a model with skyscrapers -- the third man holds a folder; the fourth man has no tie
September 7, 2006 (left to right) Fumihiko Maki (4WTC), Larry Silverstein (Developer), Norman Foster (2WTC), and Richard Rogers (3WTC). Joe Woolhead/Silverstein Properties, Inc.

Located at 250 Greenwich Strett across from the World Trade Center site, 7 World Trade Center had been destroyed by flying debris and uncontrollable fires on 9/11. Priority was given to rebuilding this area and its underground utilities. A new 52-story office tower built by the well-known Skidmore, Owings & Merrill firm officially opened on May 23, 2006 and put design architect David Childs in the good graces of Silverstein Properties.

Fully five years after the September 2001 terrorist attacks destroyed the area, the public was becoming anxious with the lack of progress. Developer Larry Silverstein was, too. By June 2005 Silverstein had gained more control over the redevelopment by introducing an elegant yet more conventional Freedom Tower redesigned by David Childs.

By December 2005 Silverstein had chosen British architect Norman Foster to design the Two World Trade Center. And then in May 2006 the developer appointed two more Pritzker Laureates — British architect Richard Rogers to design Tower 3 and Japanese architect Fumihiko Maki to create Tower 4.

In keeping with Daniel Libeskind's Master Plan for the World Trade Center site, Towers 2, 3, and 4 on Greenwich Street formed a descending spiral toward the Memorial. Towers 2, 3, and 4 were expected to include 6.2 million square feet of office space and a half million square feet of retail space.

In June 2006, the cornerstone for 1WTC was temporarily removed as excavators prepared the land for the footings to support the building. The process involved burying explosives as deep as 85 feet and then detonating the charges. The loose rock was excavated and lifted out by crane to expose the bedrock underneath. The use of explosives helped speed up the construction process and continued for two months. By November 2006, the construction crews were ready to pour some 400 cubic yards of concrete for the foundation.

On December 19, 2006, several 30-foot, 25-ton commemorative steel beams were erected at ground zero, marking the first vertical construction of the planned Freedom Tower. Approximately 805 tons of steel were produced in Luxembourg to create the first 27 enormous beams. The public was invited to sign the beams before they were installed.

2007: More Plans Unveiled

close up of muddy construction site with workers in brightly colored vests and hard hats
2007, Construction Continues at Ground Zero. Stephen Chernin/Getty Images (cropped)

Six years after the 9/11 terrorist attacks, rescue workers were becoming sick as construction workers carried on with rebuilding. The massive project was complicated in terms of architecture, construction, and human emotion. Building and planning continued.

After many revisions, World Trade Center officials unveiled final designs and construction plans for Tower 2 by Norman Foster, Tower 3 by Richard Rogers, and Tower 4 by architect Fumihiko Maki. Located on Greenwich Street along the eastern edge of the World Trade Center site, the three planned towers by these world-famous architects were designed for environmental efficiency and optimum security.

2008: Survivors' Stairs Installed

sloped metal piece in pit surrounded by construction workers
2008, The Survivors' Stairscase Is Placed in the Museum. Mario Tama/Getty Images

The Vesey Street stairway was an escape route for hundreds of people fleeing flames after the 9/11 terrorist attack. The stairs survived the collapse of both towers and remained the only above-ground remnant of the World Trade Center. Many people felt that the stairs should be preserved as a testament to the survivors who used them. The "Survivors' Stairway" was placed on a bedrock foundation in July 2008. On December 11, 2008, the stairway was moved to its final location at the site of the National 9/11 Memorial Museum, which was built around them.

2009: Skyscrapers and Memorials

close up inside sunken reflecting pool with skyscraper being constructed in background
2009, North Memorial Pool and 1WTC. Construction Photography/Avalon/Getty Images

A sagging economy diminished the need for office space, so plans were scrapped for building a fifth skyscraper. Nevertheless, construction progressed in fits and starts through 2009, and the new World Trade Center began to take shape.

The official name of Freedom Tower was changed on March 27, 2009 with the hope that One World Trade Center would be a more desireable address for businesses. The concrete and steel core began to rise beyond the reflecting pools taking shape amidst the skyscraper construction, as Maki's Tower 4 also was well underway. In August 2009, a final symbolic beam from the ground zero debris was returned to the World Trade Center site where it could become part of the Memorial Museum Pavilion.

2010: Life Restored

Worker Jay Martino looks up at one of the first Swamp White Oak trees planted around the World Trade Center Memorial Plaza. August 28, 2010
2010, First Trees Planted Around Memorial Plaza At Ground Zero. David Goldman/Getty Images (cropped)

In August 2010, the first of the planned 400 new trees were planted on the cobblestone plaza surrounding the two memorial reflecting pools. Foundation work began for Towers 2 and 3, making 2010 the first year that construction was ongoing for every individual project that made up the master plan. And then Park51 happened.

Nearby the construction site, another developer made plans to create a Muslim community center at 51 Park Place, a street near ground zero.   Many people criticized the Park51 plans, but supporters praised the idea, saying that the modernist building would serve a wide range of community needs. Protests erupted. The Park51 controversy gave life to a host of opinions and misinformation, including calling the project the "ground zero mosque." The proposed project was costly and plans changed throughout the years.

2011: The National 9/11 Memorial Opens

New York City Police Officer Danny Shea, a military vet, salutes at the North pool of the 9/11 Memorial during the tenth anniversary ceremonies of the September 11, 2001 terrorist attacks at the World Trade Center site, September 11, 2011 in New York City, 1WTC construction in background
September 2011, Dedication of the National 9/11 Memorial. David Handschuh-Pool/Getty Images

For many Americans, the killing of lead terrorist Osama bin Laden brought a sense of closure, and progress at ground zero inspired new confidence in the future. When President Obama visited the site on May 5, 2011, the skyscraper once called Freedom Tower had risen more than halfway to its final height. Now known as One World Trade Center, the tower began to dominate the World Trade Center skyscape.

Ten years after the terrorist attacks, New York put the finishing touches on the National 9/11 Memorial (Reflecting Absence). While other parts of the World Trade Center complex were still under construction, the completed memorial plaza and pools represented a promise of renewal. The National 9/11 Memorial designed by Michael Arad opened for families of 9/11 victims on September 11, 2011 and for the public on September 12.

2012: 1 World Trade Center Becomes Tallest Building

what looks like an iron goal post with a beam being lowered onto the top -- Iron workers maneuver an iron beam into place on the 100th story of a skyscraper
April 2012, One World Trade Center Becomes Tallest Building In New York. Lucas Jackson-Pool/Getty Images (cropped)

On April 30, 2012, One World Trade Center became the tallest building in New York City. A steel beam was hoisted to 1271 feet, surpassing the Empire State Building's height of 1,250 feet.

2013: A Symbolic Height of 1776 Feet

detail of very top of unfinished skyscraper, spire on top
May 2013, Final Sections of Spire Atop 1WTC. Spencer Platt/Getty Images

The 408-foot spire was installed in sections atop One World Trade Center tower. The final 18th section was put into place on May 10, 2013, making the tallest building in the Western Hemisphere a symbolic 1,776 feet high — a reminder that the United States declared its independence in 1776. By September 2013, the David Childs-designed skyscraper was getting its facade of glass, one level at a time, from the bottom up.

Four World Trade Center designed by Fumihiko Maki and Associates was issued a temporary Certificate of Occupancy, which opened the building to new tenants. Although its opening was an historic event and a milestone for Lower Manhattan, 4WTC has been difficult to lease. When the office building opened in November 2013, its problematic location remained within a construction site.

2014: Ground Zero Opens for Business and Tourism

A security guard stands inside white marble lobby, at top of stairs and escalator, near doors
November 2014, Security at Opening of One World Trade Center. Andrew Burton/Getty Images

One World Trade Center officially opened on a beautiful November day in New York City. Thirteen years after 9/11,  the publisher Condé Nast moved thousands of employees into 24 of the lowest floors of 1WTC, the centerpiece of Lower Manhattan's redevelopment.

Earlier that year, on May 21, 2014, the underground 9/11 Memorial Museum opened to the public. Forming the front yard of 1WTC, the Memorial Plaza was complete, including Michael Arad's Reflecting Absence, Peter Walker's landscaping, Snøhetta's Museum Pavilion entrance, and Davis Brody Bond's subterranean National 9/11 Museum space.

2015: One World Observatory Opens

People looking out two-story windows of One World Observatory at 1WTC, open to the public
May 2015, One World Observatory, Floors 100 to 102 of 1WTC, Opens. Spencer Platt/Getty Images

On May 29, 2015, three floors of One World Trade Center opened to the public — for a fee. Five dedicated Sky Pods transport willing tourists up to levels 100, 101, and 102 of the tallest skyscraper in America. The  SEE FOREVER™ Theater on floor 102 ensures a panoramic experience even on the most foggy of days. The City Pulse Sky Portal and floor-to-ceiling viewing areas provide opportunities for unforgettable, uninterrupted vistas. Restaurants, cafes, and gift shops are ready to suck the money from your pockets as you enjoy the views.

The controversy of the year, however, was the sudden change of architects for the yet-to-be-built Two world Trade Center. Danish architect Bjarke Ingels, founding partner and creative director of the Bjarke Ingels Group (BIG), presented new plans for 2WTC, leaving the original design by Pritzker Laureate Norman Foster in the architectural dustbin.

2016: Transportation Hub Opens

An aerial view of the National September 11 Memorial & Museum and the Oculus Transportation Hub, September 8, 2016 in New York City
March 2016, Transportation Hub Opens. Drew Angerer/Getty Images

Spanish engineer and architect Santiago Calatrava again tried to explain away cost overruns at the opening of what many call simply a subway station. For the out-of-town visitor, the architecture is unexpectedly breathtaking. When it opened in March 2016, the skyscrapers that will eventually surround it had not yet been built, allowing the architecture to soar into the Memorial Plaza. To the commuter, it is a functional building; to the taxpayer, it is expensive.

Writing in the Los Angeles Times, architecture critic Christopher Hawthorne says this: "I found it structurally overwrought and emotionally underwhelming, straining for higher meaning, eager to wring some last drops of mournful power from a site that is already crammed with official, semi-official and indirect memorials." (March 23, 2016)

Meanwhile, a design for the Performing Arts Center was unveiled in September and, right next door to the Hub, Three World Trade Center was moving upward, topping out with its last concrete bucket and highest steel beams erected by the end of 2016.

2018: Skyscrapers Compete

two skyscrapers rising from leafy trees
2018, Three World Trade Center Opens Near 4WTC. Joe Woolhead courtesy Silverstein Properties, Inc. (cropped)

Richard Rogers' industrial-looking robot-like Three World Trade Center officially opened for business on June 11, 2018. It is the third skyscraper to be built on the site of the original twin towers in Lower Manhattan. It towers over the Transportation Hub that opened two years earlier. It competes with Four World Trade Center, Maki's design that has majestically stood alone since September 2013. As the World Trade Center site becomes fully populated with new architecture, each structure changes the nature of the site.