It was a day that left the world reeling in shock.
The 9/11 terror attacks had repercussions still felt around the world today, 20 years later.
A total of 2,977 lives were lost as a result of the attacks which sparked irreversible changes to the world, not least the 20-year war in Afghanistan.
Of the total, 2,753 people were killed at the World Trade Center in Lower Manhattan, New York, when two flights intentionally crashed into the north and south towers.
There were 184 people killed at the Pentagon in Washington when American Airlines flight 77 crashed into the building.
Forty passengers and crew died near Shanksville, Pennsylvania when a flight crashed into a field.
The world watched on in horror as footage of the attacks was beamed across the globe live on TV screens.
In the days leading up to the anniversary major networks and streaming platforms are rolling out a range of programmes to commemorate the lives lost and look back on one of the darkest days in US and world history.
Not least Netflix, with ‘Turning Point: 9/11 and the War on Terror’ from which many striking images were shown from the day.
Here is a collection of images caught on 9/11 and in the immediate aftermath which remind us of why September 11, 2001, is a day the world will never forget.
10 striking images that tell the story the 9/11 terrorist attacks