People's comments have poured in sharing memories of where they were and what they were in the middle of doing when the tragic news came out.
Today, September 11, marks 20 years since the world witnessed the horror of the 9/11 attacks which were broadcast around the world.
As a result of these attacks, 2,977 lives were lost which triggered the 20-year war in Afghanistan.
The Watford Observer asked its readership to share their memories on its Facebook group called ‘We grew up in Watford’ and over 200 comments have poured in.
Caz Allen said: “When I went to pick my daughter up both towers were still standing, by the time we got home they were down. I then had the stress of trying to contact my sister who I knew was in New York for work but luckily she was safe and half way home when it happened. It’s a day I will not forget.”
Freda Clark was nervous to fly saying “we were just about to get on a plane back from Tenerife when we saw the second plane hit in the foyer of the hotel."
Mary Ryan, who was working in a friend's fancy dress shop in Galway, Ireland, said: "We closed up and went home with a friend from New Jersey who was in bits. We stayed up all night watching things unfold.
“A day or two later Vodafone gave free calls to the States for 24 hours. My friend was on my phone for 17 hours at my house. Terrible days.”
Scott Clarke said: “We landed at Gatwick from Sanford International just hours before this happened and we were going to stay a few extra days to go up the towers!”
Cathy Fitzgerald was five hours into a flight from Florida to Heathrow which was the last plane to leave before they shut down American Airspace - "I was with my three kids and we knew nothing until we landed- my husband was frantic.”
Helen Nelmes was at home but had been touring the East coast of the USA 11 days earlier and had been on the top of tower two looking over the city.
“We were on the road very close to where the aeroplane came down and we flew in and out of Boston airport, just as the terrorists flew in there too.
“We could not believe what was happening, it was like watching a film. Could not believe the horror.”
Jennifer Eglinto said: “I was training in a 26 storey building in Washington DC when the telephone rang in the classroom. I just blurted out that we had to evacuate the building because of what just happened.
"It was chaos after that. I flew back to London a couple of weeks later. I wrote a will before I flew!”
Lorna Watts, who was in Las Vegas waiting to board a flight back to the UK, said: "Clearly that did not happen and I got stuck there for another ten days. I was so scared to board the plane when it eventually left too!”
Keith Meredith, who was on the Wall St Ferry just docking in Manhattan, when the first plane hit, said: "At first we were stunned. The captain of the ferry immediately disembarked.
“We fortunately had a smart captain who had been in a gunboat during the Vietnam war.”
Neil Crabb and his wife were on the 8.30am train from Toms River NJ to the World Trade Centre Station. They were planning a day’s sightseeing starting off with the view from the top of the towers - "Needless to say we never made it to New York that day.”
Stuart Waggett said: “I was flying to Vegas for a wedding, we were in the air for three hours and then turned back not knowing what had happened until we landed.”
Maureen Devan was in America on holiday and saw it all happening in a cafe having breakfast - "Everyone was crying. All very upsetting.”
Anne Hague said: “I remember driving home in a daze and Chris Tarrant on the radio said 'go home and hug your families and loved ones'.”
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