The flame was was met by Prime Minister David Cameron earlier on Downing Street before it ended up in Hyde Park, where 60,000 people gathered to watch as the final torchbearer lit a cauldron, BBC News reports.
Earlier in the day, the royals flaunted their sporting skills – and spent some quality time with kids – at the launch of a sports-related charity.
William and Kate, both 30, and Harry, 27, visited Bacon's College to launch the Coach Core program, a partnership between their foundation and the Greenhouse charity that will help train the country's future youth-sports coaches.
They didn't just watch the action, either. On the eve of the London Olympics, William kicked a soccer ball around, Harry shot hoops in the gym and Kate tried her hand at table tennis.
"Watching me on the football field is never a pretty sight. The expression giraffe on ice springs to mind," William said in a speech later on. "Catherine, on the other hand, with a tennis racket or a hockey stick is something to behold and be aware of."
Sang Tan / AP
She praised her opponent, telling her, "You were amazing."
Hiba said, "I never thought she would be that good. It was nerve-wracking playing against her, but she was really nice so it made me relaxed."
Then Kate – in a gray dress from the store Hobbs – kicked off her wedges and stepped onto a blue gym mat to start a judo match. With a chopping motion, she proclaimed, "Hajimi," the Japanese word that traditionally kicks off the bouts.
Before her, 14-year-olds Abdurrahman Chaatouf and Aaron Mahoney-Jones bowed and showed her three the classic throws. Afterwards, Mahoney-Jones said of the royal visit: "It inspires me to know someone's behind me and behind us at Greenhouse."