The floodlights at London's 2012 Olympic stadium have been switched on at a ceremony in east London.
Prime Minister David Cameron switched on the lights at 1815 GMT and commended the team for the "great job".
Sports personalities and politicians attended the event. The site workforce, members of the local community and schoolchildren were among the audience.
Mayor Boris Johnson said it was "a historic evening" and urged people to forget the World Cup "bitterness".
Mr Cameron said: "Well done team. Great job."
The prime minister added: "In just one year, seven months, seven days, two hours and about 12 minutes, the biggest show in the world comes to town."
Mr Johnson also asked Londoners to "assuage our sense of bitterness about the Fifa World Cup" after England lost the bid to host the event in 2018 to Russia earlier this month.
Praising the Olympic Delivery Authority (ODA), Mr Johnson said: "This is a quite wonderful and historic evening and I'm so full of confidence when I look at what the ODA has achieved.
"Let me propose to you that what we need to do now to console ourselves with the unhappy events that took place in Zurich (Fifa announcement), to console ourselves the logical thing to do is, of course to bid for the London Winter Olympics. "
There are 14 lighting towers reaching 70m (230ft) above the sports area. They are supporting a total of 532 individual lights, which took sometime to warm up.
The stadium, in Stratford, has been designed to seat 80,000 spectators during the Games.
Construction is due to be finished by next summer, to allow for 12 months of testing.
The process to decide who occupies the facility after the Olympics has begun.
Applications have been submitted by Tottenham Hotspur and West Ham United football clubs.
It is hoped a tenant will be selected by the Olympic Park Legacy Company before March.