Many people were nursing foggy heads after a night of celebrations, including Martine Wright, an international marketing manager for CNET.
"I decided to have another 10 minutes in bed," she recalls. "I suppose that's what the difference was -- one decision."
Wright jumped onto the Tube's Circle line and buried her nose in a newspaper, reading about London's winning bid for the Games.
She was sitting 4 feet from 22-year-old Shahzad Tanweer.
Seconds later, at 8:50 a.m., he detonated the bomb he was carrying in a backpack
, killing himself and seven other rush-hour passengers.
"All I remember is a white light in front of my eyes, and it wasn't just a flash," Wright remembers. "I felt like it was there for a long time, and I remember looking at this white light and having this feeling of being shook from side to side."
'I couldn't understand why I couldn't move'
For Wright, there was no noise. Her eardrums had burst. And she doesn't recall the blood or pain. Her body was flung in such a way that she could not see the trauma unfolding in the rest of the carriage, save for her own.
"I couldn't understand why I couldn't move myself, and then I sort of looked up and all I could see was this metal, which was actually the corner of the Tube, that had buckled from the explosion. It looked like it was going down into the ground, but it wasn't. It was going into my legs," she says.
On top of the twisted metal, 7 feet above her, Wright also recognized one of the white gym shoes she had been wearing. But she could not compute what had happened, let alone the extent and horror of her injuries.
"My first initial reaction was, 'We've had a crash,' " she says.
Four kilometers away, lawyer Neesha Kamboj was also battling to understand why her train on the Piccadilly line had come to an abrupt halt within a minute of leaving Kings Cross station.
"We were plunged into darkness. Dense billowing smoke poured into the carriage, and it felt like the air had been suctioned out of the carriage. We couldn't breathe," she says.
Alive because she was running late
Recruitment consultant Sajda Mughal thought the train had derailed and feared she would die in a giant fireball.
"I am a Muslim by faith," she says. "I started to pray."
Little did she know that her prayers already had been answered. It was Mughal's habit to travel in the first carriage of the train, but on July 7, 2005, she was running late and had to jump on wherever she could before the doors slammed shut.
"Had I got onto that first carriage, I probably wouldn't be sat here and alive, as Germain Lindsay, one of the bombers, was on that carriage," she says.
Above ground, there was also confusion about what had happened and where.
"It came over the radio that a power surge -- it was described as -- had happened at Aldgate station," says police Senior Constable William Sargent.
The Metropolitan Police officer trains other officers in crowd control, and he had been waiting for a group of anarchists to arrive at Euston station from protesting at the G8 conference in Scotland.
Instead, he found himself coordinating logistics for the emergency services response to the unfolding crisis, which he initially thought was an elaborate training exercise.
"My eyes were drawn to the entrance to the station. People were coming out with blackened faces. I looked at their faces and thought, 'That makeup is really good,' " he remembers.
Reality soon dawned.
"The injuries were quite horrendous."
Still, it was only when Transport for London worker David Boyce, then 25, entered the carriage Lindsay had been riding in that it became clear that terrorists had targeted London commuters.
He was the first on the scene and describes devastation.
"I stepped onto the train and could see bodies and body parts all over the place," he says. "The first person I came across was a gentleman called Gary who was on a seat, so using some of my own clothes, I tourniqueted his legs because they had come off."
Boyce made his way around the many injured, doing what he could to help.
"It was only while I was saving these people's lives that I realized this massive hole in the floor and the ceiling, and it was unmistakably a bomb," he says.
There had been three simultaneous attacks on the underground rail system, and even as emergency services frantically worked to rescue survivors, another bomb exploded.
This time, it was on the streets of London.
At 9:47 a.m., 18-year-old Hasib Hussain killed himself and 13 other travelers on the No. 30 bus in Tavistock Square.
"We arrived to see the roof missing off the bus," recalls London firefighter Stephen McDermott.
"While I was helping a paramedic, one lady died right there in front of me, and I looked at her finger and she had a wedding ring on. You are thinking, 'She is obviously married, does she have children? Is Mum not coming home tonight?' "
One of the lucky ones
Meanwhile, back at Edgware Road, Wright was still fighting for her life.
Trapped by the metal in her legs, firefighters had to cut her out of the wreckage, and she was the last survivor to be rescued from the underground.
By the time she was brought to the surface, Wright had lost 80% of her blood. She would also lose both legs.
She credits her survival to off-duty police officer Liz Kenworthy, who happened to be on the same train and was the first person to render aid.
Wright considers herself one of the lucky ones.
Ten years on, she is now a mother, an inspirational speaker and Paralympian, making her debut in the 2012 Games she had vowed to get tickets for just moments before the bombing.
"I truly believe I was always meant to make this journey," she says. "My son was born on July 7. I now wear number seven. I chose that. I wear that on my shirt. I am now captain of the Great Britain Sitting Volleyball team, and I wear that because I truly believe that is my lucky number, and it is also a testament and a memory to all of the people who lost their lives that day."
'London kept moving'
In all, the four Islamic suicide bombers from Leeds had killed 52 people and injured more than 700 others in their wave of terror across London on July 7, 2005.
Ten years on, the devastation has not been forgotten, but what so many survivors and rescue workers also remember is the solidarity that followed.
"My most significant experience of 7/7 is how London came together," says Mughal, the commuter who was running late. She has since established the JAN Trust, which works to empower women and prevent radicalization. "I remember everyone just rallying around to help people."
Sargent, the Metropolitan Police officer, remembers that support well: "Every time we drove past a crowd of people, they would applaud us -- just thankful we were there."
For Boyce, the Transport for London worker, the camaraderie of Londoners has also been the most poignant memory of that day.
"I think it showed London is pretty resilient," he says. "Everyone did everything they could to help everyone. The humanity was brilliant and, you know, London kept moving afterwards."