The first anniversary of the 7 July bombings of London will be marked by a national two-minute silence.
Plaques will be laid to remember the victims
The silence, at 1200 BST on Friday, is part of a day of events to commemorate the attacks and remember the victims.
Memorial plaques will be laid at the blast sites, with survivors and victims' families invited to view them.
The day will end with a public ceremony at Regent's Park in west London at 1800 BST, when the names of the 52 people who died will be read out.
Culture Secretary Tessa Jowell, responsible for organising the events, said the attacks were a "dark hour in our history".
"Two minutes of silence at noon on 7 July will bring the whole nation together to pay tribute," she said.
The bereaved families, the suffering of the injured, and all those who selflessly aided them would be remembered, she said.
"The silence, the permanent memorial and the commemoration will give us all a way to remember the dead and give a voice to what is still unutterable grief."
The book of tributes will be laid at the Museum of London
The day of remembrance will begin with Ms Jowell, London mayor Ken Livingstone and the capital's transport chief Peter Hendy laying flowers at King's Cross station to coincide with the timing of the attacks.
Mr Livingstone and Mr Hendy will later lay flowers in Tavistock Square, a year to the minute after a bomb exploded on a number 30 bus.
Plaques carrying the names of all those who died in the explosions will be laid at King's Cross, Russell Square, Edgware Road and Aldgate Tube stations, and at Tavistock Square.
Identical plaques are being placed at Russell Square and at King's Cross because victims of the attack on the Piccadilly Line train emerged from both stations.
The relatives of those killed will be invited to several private events, including a lunch provided by Transport for London (TfL).
Some will also attend a ceremony at St Ethelburga's church in the City of London and the Museum of London, where a book of tributes will be laid.
The Regent's Park event will include a performance by the London Gospel Choir and a welcome speech by Ms Jowell.
London mayor Ken Livingstone will attend the commemorations
There will be readings by relatives before BBC newsreader Peter Donaldson recites the names of the 52 dead.
All 1,000 survivors and relatives of those killed have been invited to the Regent's Park event.
Trydydd, a vocal group of three female singers from London, will perform Song of Doves, written by the family of King's Cross victim Helen Jones.
Throughout the day, the public will be encouraged to place a flower in a mosaic in Regent's Park, which will be completed at the commemoration service.
The 7 July Assistance Centre helpline - 0845 054 7444 - is available to provide advice and support to anyone who is affected by the events of 7 July or the anniversary.