The Olympic Flame will arrive in the UK on Friday night after it was handed over at a ceremony in Athens.
British delegates including David Beckham fly back from Greece to RNAS Culdrose in Cornwall.
They will attend a special ceremony welcoming the flame, before it is taken on a 70-day relay involving 8,000 torchbearers covering 8,000 miles.
The flame will finally reach east London's Olympic Stadium and the opening of the Games on July 27.
London was officially handed the flame on Thursday in a rain-hit sundown ceremony at the old Panathenaic Stadium, venue of the first modern Olympics in 1896.
The flame was handed to the Princess Royal, who was watched closely by other members of the official delegation including London 2012 chairman Lord Coe, Olympics minister Hugh Robertson, London mayor Boris Johnson, former England football captain David Beckham and five British sporting teenagers.
In his speech, Lord Coe thanked the damp crowd for Greece's warm hospitality and also for "laying on the British weather for us".
He added that the arrival of the flame on British shores will be a "resounding clarion call" to the world's top athletes to gather for the Games, and millions of Britons have been working hard to create a great welcome.
"If the Olympic Games are about celebrating the best athletes in the world, the Olympic spirit is about celebrating the best in ourselves and in our communities," he said. "We have found the very best torchbearers who, like Olympic athletes, will inspire a generation.
"As we prepare to bring the flame to the UK, we are reminded of our responsibility - like that of our predecessors in 1908 and especially 1948 - to stage Games that use the power of sport to unite the world in a celebration of achievement and inspiration in challenging times. A Games that will inspire the next generation to choose sport."