The 1990s was when New York city’s skyline would not have been perceived without the Twin Towers, known as the world’s tallest structure. The architect Minouro Yamasaki made an immense mark on the skyline of one of the world’s richest cities. The architect transformed the concept of the complex building into the tallest structure in the world. Twin towers revolutionized the concept of skyscrapers and building high, these towers were basically  “steel tubes”. The steel bracing lined the exterior of the building, connecting it to the core of the building which was made out of 47 steel columns braced with sheetrock. The tower connected the exterior to its core via the floors. 

The building was notorious for its inhumane scale and anti-urban qualities during his lifetime. Although the design of the skyscraper seemed to be minimal, the gigantic scale and the idea of the ultra-high building seemed manipulative and dehumanizing as they reduced individuals to an insignificant scale. 

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Newyork before the 9/11 terrorist attack_©Reddit

Despite the towers draining out the urban spirit, leaving it to an isolated enclave, these extremely high towers portray the USA’s wealth, power, and authority. The incident of the world trade center entirely changed the perspective, the towers that were once considered as the bete noire of planners suddenly became the symbol of strength. As if the attack was perfectly planned. 

One of the hijackers (Muhammad Ata) was himself an architectural graduate from Cairo’s architectural school and was perfectly aware that the building was a political agenda and deleted from existence. As if he had been listening to the debate (Sudjic, 2006).

9/11 Terrorist Attack

The 9/11 terrorist attack on the World Trade Center, grabbed the attention worldwide. The attack questioned the safety of skyscrapers and the future of tall buildings. Although the collapse of the 110-story building in lower Manhattan changed the perception of the twin tower amongst the nation and was signified as a symbol of Power. Since then the urge to build high has never diminished and the lust to control has been captivated. The attack on the twin tower revolutionized the design of tall buildings. 

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9/11 attack on Twin Tower_©Robert Giroux- Getty images

The planes that crashed into the twin towers were moving over 400mph, the twin-engine,737 passenger jet crashed into the building. Despite the damage on the outside and inside cores the building stood still due to redundancy. The weight of the building shifted towards the unaffected columns, but the plane crash scraped off the fire coating leaving the building to get heated up due to its steel-framed structure and catching fire. The floors above the impacted area weakened to support the structure and the building collapsed (Cheddar, 2021).

Change in Skyscraper design after 9/11

It has been over two decades since the incidents and the world has seen even bigger buildings. The tall buildings and skyscrapers still portray the progress and wealth of a country. After the attack, the architects started to perceive things in terms of durability and safer buildings.

Even Santiago Calatrava, who designed the St. Nicholas National Shrine at the world trade center, says what happened in NewYork in 2001 surely impacted his practice as an architect as well as an engineer, He believed that due to the availability of new materials, reinforcements, and reimagining the flow within the space has become the integral core of designing.

Buildings built after the attack have greater safety protocols and stronger materials. Most high-rise buildings nowadays use concrete walls within the core and steel on the outer perimeters. For instance, the new world trade center has a 3-foot thick core made out of concrete and skin made out of glass. Concrete is far more fire-resistant than steel, making the building much more durable. 

The Calatrava’s oculus adjacent to the 9/11 memorial, was modified structurally, as per the orders of the New York Police department. He included reinforcements to support the structure of the wings in order to improve the blast resistance (Quito, 2021).

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The oculus_©Getty images


The 9/11 incident gave rise to many concerns regarding the safety of human lives in tall buildings. The debate after 9/11 revolved less around structural choices but more on means of egress. People need to feel safe in tall buildings, and the measures taken to improve the safety in these high rises changes the perception in people’s mind

In newer buildings improved safety and security conditions, including the additional and widened stairwells, emergency lightings, thicker glass, and reinforced concrete allowed people to restore their faith in tall buildings.

Present-day Newyork_©Reuters

A better understanding of progressive collapse and structures allowed architects to build a variety of creative forms and even taller structures (Krauth, 2021).


  1. Cheddar (2021). How 9/11 Changed Skyscraper Design – Cheddar Explains. YouTube. Available at: [Accessed 2 Oct. 2021].
  2. Krauth, D. (2021). 20 Years Later: Are Tall Buildings Safer after September 11? [online] ABC7 New York. Available at:
  3. Quito, A. (2021). The Hard Lessons of Sept. 11 Led to the Boom in Supertall Skyscrapers. [online] Quartz. Available at: [Accessed 13 Mar. 2022].
  4. Sudjic, D. (2006). High-Rise Syndrome. In: The Edifice Complex. Penguin Books, p.Pg: 397-429.

Romaisa Tahir ( a student of architecture at the Institute for arts and culture, from Pakistan) enjoys writing and expresses her concerns via poetry and narrative writing. She believes that the passion for writing and admiration for the art of building can be blended; allowing the silence of buildings to speak through words and add meaning to their existence.

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