FLASHBACK | 9/11 attacks: Where were you on 11 September 2001?

Twenty-five years ago, the world watched in disbelief as New York’s skyline was transformed by an attack that would change the course of history.

On 11 September 2001, 19 terrorists linked to al-Qaeda hijacked four commercial passenger aircraft in a coordinated attack on the United States.

What began as an ordinary Tuesday morning quickly became one of the most devastating days in modern history.

READ | New York marks 25th anniversary of 9/11 attacks

Everyone remembers where they were that day

I had just moved from Cape Town to London a couple of months prior. I was working in Kew Gardens and on a phone call to an at-the-time unemployed friend who was busy sending out her CV – while watching TV.

While on the call she casually mentioned that a plane had crashed into a building in New York.

Shortly thereafter she mentioned that another plane had crashed.

It quickly dawned on us that this was no accident.

Shortly thereafter we were told to pack up and leave and head home. But was London the next likely target? Where the busses, trains and underground safe to use?

Cautiously I made it back to Southfields and switched on the TV to watch the drama unfold.

The first plane

At 08:46, American Airlines Flight 11 crashed into the North Tower of the World Trade Center in New York.

At first, many people believed the incident could have been a terrible aviation accident.

Emergency crews rushed towards the burning tower as people inside began evacuating. Firefighters, police officers and paramedics entered the building as others fled.

Then, at 09:03, the unthinkable happened again.

United Airlines Flight 175 slammed into the South Tower.

The second impact made it clear that New York was under attack.

The two enormous towers, symbols of American economic power and landmarks recognised around the world, were engulfed in smoke and flames.

The attacks spread

At 09:37, American Airlines Flight 77 crashed into the Pentagon, the headquarters of the US Department of Defence, near Washington, DC.

Another hijacked aircraft, United Airlines Flight 93, was heading towards Washington.

But the passengers and crew aboard Flight 93 learned about the other attacks and attempted to take control of the aircraft.

Their actions prevented the plane from reaching its intended target. At 10:03, Flight 93 crashed into a field near Shanksville, Pennsylvania.

There were no survivors.

The towers collapse

At 09:59, less than an hour after being struck, the South Tower collapsed.

The enormous structure disintegrated into a cloud of dust and debris, sending people running through the streets of Lower Manhattan.

Twenty-nine minutes later, at 10:28, the North Tower also collapsed.

The World Trade Center complex was devastated.

For the thousands of people caught inside the buildings and surrounding streets, there was suddenly nowhere safe to go.

Meanwhile, firefighters, police officers, paramedics and other emergency workers continued moving towards the disaster zone.

Many would never return home.

Almost 3 000 lives lost

The attacks killed 2 977 people, with victims at the World Trade Center, the Pentagon and near Shanksville. Thousands more were injured.

The victims came from different countries, professions, backgrounds and generations.

Among them were office workers beginning their day, passengers travelling across the country, people working in restaurants and businesses, and emergency responders who had rushed towards the danger.

The New York City Fire Department suffered particularly devastating losses.

The scale of the tragedy became clearer as the rescue operation turned into a recovery operation.

A city covered in dust

In the hours and days that followed, Lower Manhattan became a landscape of twisted steel, concrete and dust.

Families searched desperately for missing relatives.

Photographs of loved ones were posted around the city. Hospitals waited for survivors. Rescue workers searched through the ruins.

The recovery operation at Ground Zero ultimately continued for nine months, ending on 30 May 2002.

But the consequences of 9/11 did not end when the rubble was cleared.

Thousands of first responders, survivors and people who lived or worked in Lower Manhattan were exposed to toxic dust and other hazards.

In the years that followed, many developed serious illnesses linked to the attacks and their aftermath.

The world changed

The attacks triggered profound changes in American foreign and domestic policy and reshaped international relations.

The United States launched its global campaign against al-Qaeda and its allies, while the invasion of Afghanistan followed weeks later.

Airport security changed dramatically. International intelligence and counterterrorism operations expanded. Wars that followed would affect millions of people around the world.

But beyond politics and military strategy, 9/11 left an enduring human legacy.

For survivors, families and first responders, the memories remain deeply personal.

Remembering those who never came home

Today, the site where the Twin Towers once stood is home to the National September 11 Memorial & Museum.

Two enormous memorial pools occupy the footprints of the former towers, with the names of those killed inscribed around them.

Every year, the names of the victims are read aloud during the anniversary commemoration.

The moments of silence mark the key moments of that morning: 08:46, 09:03, 09:37, 09:59, 10:03 and 10:28.

Twenty-five years later, the images remain familiar: the burning towers, the smoke rising over Manhattan, people running through the streets and emergency workers climbing towards the danger.

Where in the world were YOU on that fateful day, 11 September 2011?