For those affected by the London bombings, the service in Regent's Park on the evening of 7 July marked not only the end of a long day, but the conclusion of a long and unbearably painful year.
Many in the crowd were moved to tears
As one survivor put it, the anniversary represented a "watershed". The pain remains, but for some there is a feeling of moving on.
"I've been through two weeks of hell and anxiety about the anniversary coming up," said Michael Henning, who survived the Aldgate bombing.
"But this morning I woke up feeling extremely calm, and a lot of other survivors have said the same. We think it's because we made it to the anniversary, it's a kind of watershed."
For John Falding, who lost his girlfriend Anat Rosenberg, there was some kind of relief at having got through the day.
"But tomorrow the excitement, if you can call it that, will be gone and it will be back to coping with things on my own," he said.
The service had opened, under the clouds, with a spine-tingling rendition of Something Inside So Strong by the London Community Gospel Choir.
Ellen Boyle, right, heard she had breast cancer on 7 July last year
And the tears began to flow. Some of those members of the public who came to remember would have known someone caught up in the bombings, others came simply to show their solidarity.
Among the survivors and relatives - in a separate enclosure - the sound of the choir, dressed all in white, was enough to break the resolve they had shown minutes earlier as they filed into their seats.
"As soon as the choir started all the emotion came out in floods," said Mr Henning.
"The tissues were being handed round."
The public had come in their hundreds - workers in business suits, mums with buggies, students, clergymen and women. The crowd reflected the diversity of the 52 killed one year earlier.
Each had their own reason for being there.
On 7 July last year, as the bombs wreaked havoc underground, 53-year-old Ellen Boyle was in London's St Thomas's Hospital, being told she had breast cancer.
She emerged, reeling, to find chaos outside. She and her friend Marion Woodward, walked home to Brixton, trying to take in both a personal tragedy and a public outrage.
A year on, after a "horrendous" 12 months involving major surgery and chemotherapy, Ellen is a survivor too.
"That day we just wandered around feeling surreal. Today is a sombre day, we came to mark that really," she says.
Marion adds: "We just feel so sorry for everybody who was affected. We came here to bring flowers, it's a silly thing really but you don't feel you can do anything else."
Behind them a solitary older gentleman in a suit walked through the park gate towards the gathering crowd. Graham White, 57, whose son lost his partner Jennifer Nicholson in the Edgware Road bombing, had come from work to pay his respects.
His son would be watching from a separate section for the bereaved, but later they would travel back to Gloucestershire together, he said.
"They had been together for four or five years, after meeting in the first year at university. He moved back home after Jennifer died, he didn't want to stay on in the house they had shared in Reading," he added.
A group of Muslim friends was there to tell people about their campaign
Nearby a group of young Muslim men from Nottingham were handing out yellow and black wristbands. They each wore a tee-shirt bearing the slogan 'We're Not Afraid - Beat Terrorism'.
They work on their fledgling campaign - which is separate from the website of the same name - in their spare time, and aim to raise money for the London Bombings Relief Fund, Red Cross and Unicef.
"We're also fed up with the image being portrayed of Muslims and we want people to know not all of us are bad," says Suhail Butt, 28.
Teacher Shopna Alom, 22, and her 16-year-old pupil Khatija Hafesji are also Muslims. As Londoners they came because they feel part of what happened and believe it's important to mark the day.
"Within the Muslim community people are more outspoken about things now. If we talk about politics in the mosque, it's more acceptable than it was," says Khatija.
"After 9/11 people were in denial that we had a problem."
After the gospel choir there was quiet, as the crowd heard readings from four of the bereaved. For just a few moments, their intensely personal thoughts were shared with the nation.
Then as the names of the 52 people killed were read out it seemed no-one was even taking a breath.
Later the scale of personal tragedy hit home as those who had survived or lost loved ones queued to add a yellow gerbera to the middle of a giant floral tribute.
The ceremony was open to all who want to remember the victims
The first flower was laid by Yvonne Nash, who lost her boyfriend Jamie Gordon in the No 30 bus bombing, and whose friend had come up with the idea for the mosaic.
The silent line of mothers, fathers, brothers, sisters, partners and children stretched far behind her.
And they kept coming until the display was complete. Afterwards, groups of people hugged and broke down in tears.
Then the changeable British summer weather did its bit to round off a painful and emotional day of remembrance.
As the mosaic took its final shape, with the Thoresby Colliery Band belting out a rousing tune in the background, the sun finally forced its way through the gloom.