Police helicopters hovered overhead as London Mayor Ken Livingstone placed a wreath of flowers outside King's Cross station, where the four attackers separated before detonating their bombs, at 8:50 a.m. - the moment three of the explosions went off on July 7, 2005.
Relatives of those who died were invited to attend an evening ceremony in Regent's Park, where the names of the dead were to be read aloud.
A year after the attacks, life in the capital has returned to normal, almost.
But the fear isn't gone, only covered over by a veneer of calm, an uneasy sense of normality that could be shattered by another attack.
Memories of the ordinary Thursday morning commute that turned horrific are never far from the surface. And the attacks, which killed 52 commuters plus the four bombers, have changed Britain in ways large and small.
News that the young attackers were all born or raised in Britain stunned many and strained ties between the country's large Muslim community and the wider population.
Many British Muslims feel they're targets for suspicion; rights activists fear new anti-terror powers threaten civil liberties; and two mistaken shootings by officers have undermined public trust in the police, the AP reports.
Within days of the bombings, detectives identified those they believed responsible - four young men dead in the wreckage with their victims. Three were of Pakistani descent and lived in and around the northern English city of Leeds. The fourth was a Jamaican immigrant who settled northwest of London.
But a year later, police don't know to what extent others may have aided them and the search for a wider network appears stalled. No one has been arrested as a suspected co-conspirator.