Relatives of the 52 victims of the 7 July bombings marked the fourth anniversary of the attacks today with the unveiling of a memorial commemorating their loved ones.
They were joined by the Prince of Wales, Prime Minister Gordon Brown and other political leaders as the nation remembered those killed and injured in the atrocities on London's transport network in 2005.
A monument honouring the dead and costing nearly £1 million has been created in Hyde Park - 52 stainless steel columns, or stelae, 11.5ft (3.5m) tall.
Each one is unique and they have been grouped together in four clusters, reflecting the separate locations of the bombings - Tavistock Square, Edgware Road, King's Cross and Aldgate.
Four suicide bombers detonated their rucksack devices near these locations on the morning of 7 July 2005, killing the 52 and injuring hundreds of others, some seriously.
A stainless steel plaque naming all those who died has also been erected at the memorial site between the park's Lover's Walk and Park Lane.
Saba Mozakka, 28, one of six relatives on the memorial's project board which helped create the monument, said: "We think it is truly incredible and reflects the importance of the people commemorated."
Ms Mozakka's mother, Behnaz Mozakka, 47, a biomedical officer, was killed on the Piccadilly line Tube while commuting to work.
She added: "One of the fantastic things about the monument is that it reflects the individual and the collective and shows the connectivity of events."
She added: "I think and hope people will feel passionately about the memorial when we open it."
Mr Brown, Tory leader David Cameron, Liberal Democrat leader Nick Clegg, London Mayor Boris Johnson, humanitarian assistance minister Tessa Jowell and senior figures from the emergency services and representatives of other organisations attended the unveiling ceremony.
Mr Johnson said: "This memorial echoes the steely determination shown by Londoners in the days following the bombings.
"We have done much to make London safer, but today reminds us that London's strength ultimately lies with its people."
There was a relaxed atmosphere in Hyde Park before the unveiling ceremony began.
Relatives of the bombing victims sat and chatted close to the memorial, drinking tea and eating pastries as they waited for the day's events to begin.
Nearby, a 10-piece brass ensemble from the Guildhall School of Music entertained them with well-known tunes and, for a while, the sun shone before showers sent people scurrying under trees for shelter.
Former London mayor Ken Livingstone was among the 700 invited guests, who included survivors and victims' relatives.
He praised the striking design for the memorial, saying: "I think it's just exactly right. Often, it's very difficult to do something like this and get it right, but I think everyone has done a great job."
Speaking about the actual day when the devastating bombs exploded, Mr Livingstone said: "On the day, what drives you is the work that's got to be done, but, in the weeks and months afterwards, I met many families at various memorials and it was all incredibly painful."
Tory leader Mr Cameron also had a positive response to the monument.
He said: "I think it's very brilliantly put together.
"It seems also very fitting the way they've grouped the columns around the four areas where the bombs went off.
"Talking to some of the bereaved, they were all involved in this design and all like it and you can see people reacting to it positively.
"They're walking up and touching it - it's very positive and very good."
As the families waited for Charles and the Duchess of Cornwall to arrive, many spent time walking around the 52 stainless steel columns, running their hands over the surfaces of the metal structures and also reading the names inscribed on a plaque nearby.