By Emma Griffiths
BBC News website, London
Thousands of people packed into the square
It was standing room only in Trafalgar Square on Thursday evening as thousands of people shouldered their way in to attend a vigil for last week's bomb victims and applaud calls for unity among Londoners.
The mood was calm, people chatting among themselves while waiting for the speakers to begin.
Some had been in the square since the two-minute silence at noon, others were clearly tourists who had got caught up in events while visiting the square.
Cyclists and students lined up alongside men in suits and others in bandanas along the square's steps, fountains and walls.
Clusters of matching signs could be seen held above the heads of the crowd.
To one side were A4 sheets saying simply "Peace", to the back were groups of white balloons. But by far the most numerous were banners reading: "Students against terrorism, against racism, against war".
Many non-students were happy, in a gesture of solidarity, to hold the banners, apparently handed out by the National Union of Students.
Among them was Alison Cameron, 39, from Chelsea, who suffered post-traumatic stress a few years ago after identifying her colleagues' bodies when they drowned in an accident in Belarus.
Many people carried the NUS banners in a show of solidarity
"I very much identify with the families and the people involved in the aftermath because I know how traumatic it can be, what a devastating effect it can have on people's lives," she told BBC News.
"An event like this is very important for this city, so we can put it behind us and carry on living."
Queues of people on two sides of the square waited in soaring temperatures to sign the books of condolence.
Sister Margo Murphy, 60, who belongs to Our Lady of the Mission, an international religious congregation with a base in Harrow, had been queuing for half an hour.
"We have had messages throughout the week from our convents all over the world expressing their sorrow and pain and love for the people of London," she said.
"I felt it was important in a sense to bring that [message] here."
Some packed out the square to see the speakers line up by the "London United" signs in front of the National Gallery - others chose to shelter in the shade or dip their feet in the fountains.
As an audibly emotional Ken Livingstone, mayor of London, took the stand as first speaker, he was greeted by a huge round of applause and an attentive crowd.
They seemed to appreciate his message of unity and his praise for London's tolerance and diversity.
He looked back to bombing campaigns London has survived in the past, and looked forward to the London Olympics in 2012.
"In seven years' time, when the Games begin, sitting at the front of the stadium, and watching the 200 teams that will come from every nation, will be those who were maimed but survived, and the relatives of those who died," he said.
Sandy Dunn created her own tribute to the victims
"Those who came here to kill last Thursday had many goals, but one was that we should turn on each other, like animals trapped in a cage, and they failed, totally and utterly."
Speakers - ranging from celebrities such as newsreader Sir Trevor McDonald and London Olympic bid chairman Seb Coe, to leaders of different faiths and emergency services workers - did readings stressing the theme of togetherness.
The crowd listened patiently and applauded each speaker.
But in the south-west corner of the square, Sandy Dunn, from Camden, north London, felt the arrangements had been inadequate.
She had been sitting since 11.30am surrounded by a collection of newspaper cuttings, candles, flowers and hand-made signs she had constructed for the vigil.
"I did it quickly this morning - I just feel it was a catharsis I suppose, the need to get it out, come down here and do it. It would've been easier not to but I'm glad I did," she said.
"The mayor should have the photos [of the missing and dead] up - there should be something more."