It was a birthday present – a trip to New York for my brother and I, from our mum and dad.
On day three of our dream holiday, we'd just finished breakfast and were catching a helicopter for a tour of the city, when I overheard somebody say 'it's on fire'.
A crowd had gathered by the lifts and I said 'what's going on', somebody said: 'One of the Twin Towers is on fire, we're going up the lift to the top floor to have a look'.
Our hotel was on Sixth Avenue and 32nd Street, not too far from Ground Zero but far enough for us to be safe. From a very naive and innocent perspective, we decided to catch a cab down to the Twin Towers to have a closer look.
By the time we got outside, the other tower was on fire.
The general impression at this time was that it was a tragic accident, a small plane had suffered a mishap and had flown into the tower.
Everyone was still going to work, meetings and the shops. Business as usual.
We decided to walk down and made it to Fifth Avenue and 1st Street to where there was a police cordon, camera crews and onlookers.
The situation was now very different.
We could see the size of the hole in both towers. News outlets were reporting it was a suspected terrorist attack and we could see objects falling from the towers. Later, we realised these were people.
I said 'let's get back, that one wobbled, if they fall, they'll hit us' and just as my brother said 'they're built not to fall', the first tower collapsed in on itself.
And then within minutes, we watched as the second one fell and the hundreds of people in the street went silent.
There was a collective realisation that thousands of people had just died.
I turned to my brother and said 'let's get back to the hotel'.
There were a lot of people crying but a lot of anger too.
By the time we reached the hotel, the jets were flying overhead, the army were moving into position and the city was in lockdown.
We spent the next few hours watching the full horror unfold on the television in the hotel lobby.
Eventually, we got out of New York but not for another five days.
Richard Irvine worked at The Chronicle's old Commonhall Street HQ at the time of the attacks and emailed first-hand accounts of his experiences in New York back to the office. He is now a multimedia desk editor for our sister paper, the Liverpool Echo.
