London: Olympics legend Nadia Comaneci held the 2012 torch aloft over London as the flame began a seven-day tour of London that will culminate at the Games opening ceremony. (Agencies)
Olympics organisers hope that with the flame now in the British capital, attention will turn towards sport and the final countdown to the Games -- and away from the security and transport fears that dogged the last week.
Comaneci, the perfect 10-scoring Romanian gymnast who won five gold medals over the 1976 and 1980 Olympics, passed the flame on to British ex-NBA basketball star John Amaechi atop the North Greenwhich Arena -- the former Millennium Dome -- which will host the artistic and trampoline gymnastics as well as the basketball finals.
British triple jumper Phillips Idowu, a Beijing silver medallist tipped for gold in London, and footballer Fabrice Muamba, who suffered a heart attack during an FA Cup match in March, were among Saturday's other torchbearers.
The flame was kept at the Tower of London on Friday night, where the British sovereign's ceremonial jewels are kept, following a dramatic arrival in the city, a week ahead of the opening ceremony next Friday.
It was flown in on a Royal Navy helicopter and lowered to the ground by a marine commando carrying it in a miner's lamp attached to his waist.
The final seven days in London are the culmination of an 8,000-mile (12,800-kilometre) journey around Britain that has taken the flame within an hour's travel time of 95 percent of the British population, taking in famous sports venues, historic sites and places of outstanding natural beauty.
Its 36-mile (58-kilometre) tour Saturday around eastern London started at the Royal Observatory, Greenwich, located astride the world's prime meridian. Schoolgirl Natasha Sinha, 15, started the relay at 7:20 am.
Robin Knox-Johnson, the first person to sail solo non-stop around the world, carried the torch on a lap of the nearby Cutty Sark, the tea clipper ship which has undergone a £50 million renovation following a fire in 2007.
Comeneci then took the flame to the top of the North Greenwich Arena.
"I'm happy that I had the honour to carry that in such an unusual way," the 50-year-old told BBC television on top of the 20,000-seater venue.
"London is doing great. Everybody is ready for it, everything is prepared, some of the athletes already arrived and they are excited to start to compete and the entire world will be here so there's not a better place to be right now."
Local boy Idowu carried the torch through the Westfield shopping centre near the Olympic Park and appeared overwhelmed by the support of the crowd.
"Being born, raised and schooled in east London, having the opportunity to carry the Olympic torch in the home Games in front of my east London people... It's an amazing feeling. I'm full of emotion," he said.
Inside the Olympic Park, competitors were settling in, while the Australian women's hockey team was out on the practice pitch.
There was even sunshine -- a welcome sight after a week of miserable weather.
Also in Saturday's relay were the oldest and youngest torchbearers, with 101-year old marathon runner Fauja Singh and schoolboy Chester Chambers, 12, taking part.
Muamba was the last torchbearer of the day in east London's Walthamstow, where he grew up after moving to Britain from the Democratic Republic of Congo.
The 24-year-old, whose heart stopped for 78 minutes after he collapsed on the pitch, has made a remarkable recovery and was on Saturday able to run with the flame in front of crowds of flag-waving suppporters.
As he lit a cauldron with the torch he described it as "a special day", adding: "What happened to me it's a miracle... and I thank God that I'm alive... that I'm still able to do this."
Last week's headlines were dominated by Britain having to send an extra 3,500 troops to the Games -- taking the full deployment to 17,000 -- after private security firm G4S admitted they could provide the full contingent of guards.
London: Olympics legend Nadia Comaneci held the 2012 torch aloft over London as the flame began a seven-day tour of London that will culminate at the Games opening ceremony.