LONDON (CNN) — Excitement is building across Britain as it prepares for the official start of the Summer Olympic Games on Friday night.

One of the biggest secrets in London will finally be revealed as what organizers expect to be a billion people worldwide watch the opening ceremony created by Danny Boyle, best known for the Oscar-winning film “Slumdog Millionaire.”

Meanwhile, the day got off to a resounding start as bells around the country pealed for three minutes, including more than 40 chimes from London’s famous Big Ben clock tower.

The Olympic torch, which has traveled around the United Kingdom over the past 70 days, then set off on the final leg of its journey toward Olympic Stadium, aboard the royal barge Gloriana.

Rowers propelled the vessel, which played a central role in Queen Elizabeth II’s diamond jubilee celebrations, down the River Thames from Hampton Court to Tower Bridge.

Former Olympian rower Matthew Pinsent, tasked with carrying the flame on to the barge, said it was “a huge day for London.”

Crowds lined the river’s banks to cheer the torch along, adding to the more than 13 million who’ve turned out to watch it pass in the course of its 8,000-mile journey, according to the government.

International Olympic Committee chief Jacques Rogge declared the capital all set to host the world’s greatest sporting event.

The IOC has “reviewed all the operational items, and I can say with pleasure that London is ready and we are eagerly waiting for the opening ceremony,” he told reporters.

Just over 7,000 of the 10,500 athletes taking part in the Games have now arrived in the United Kingdom, the British government said.

U.S. first lady Michelle Obama met with members of Team USA at a breakfast Friday morning at the U.S. Olympic Training Facility, hours before she will lead the delegation as the athletes parade at the opening ceremony.

Katie Lawrence of Georgia, who holds dual U.S.-British citizenship, told CNN she was hugely excited to be in London to watch the sporting extravaganza.

“I love the Olympic Games, I always have, always will. I’m always torn as to which team to root for, but I have no shame in rooting for both USA and GB,” said Lawrence, who saw the 1996 Games in Atlanta as a child. “I cannot wait to be immersed in all of the excitement and bustle that the Games bring.”

CNN iReporter Kevin Dunscombe, a Londoner, is excited by the Games and “very proud” of London as the host city.

“I really felt the buzz of the Olympics when I walked through Trafalgar Square on my way home last night,” he said Friday. “The atmosphere was really electric and this is before the Games have actually begun!”

UK national newspaper headlines have heralded the day as the start of something truly special. “Get the party started,” reads the Telegraph, while the Times of London hails “The world in one city.” The Guardian strikes a more reflective note as London prepares to host the Games for a third time, saying, “Time to find out who we are.”

News reports also have picked up on the verbal to-and-fro between British Prime Minister David Cameron and Republican U.S. presidential candidate Mitt Romney, who appeared to question London’s readiness while on a UK trip — and then had to backtrack.

“You know it’s hard to know just how well it will turn out,” Romney said in an interview with NBC News on Wednesday evening. “There are a few things that were disconcerting. The stories about the private security firm not having enough people, the supposed strike of the immigration and customs officials — that obviously is not something which is encouraging.”

A day later, in what sounded like a jab at Romney’s own stewardship of the 2002 Olympics in Salt Lake City, Cameron appeared to draw a contrast between staging the Games in London versus Utah.

“We are holding an Olympic Games in one of the busiest, most active, bustling cities anywhere in the world. Of course it’s easier if you hold an Olympic Games in the middle of nowhere,” he said.

After meeting with Cameron, Romney praised British preparations for the Games. He then sidestepped a question about whether he intended any criticism of London in his initial comments, saying he expected the Games to be “highly successful.”

Speaking to CNN’s Piers Morgan in London on Friday, Romney also said he was “delighted to see the kind of support that has been around the torch, for instance.”

Forecasters at Britain’s Met Office say rain showers over London should clear by evening, allowing those who have coveted tickets to watch the opening ceremony at the stadium to stay dry.

Few specifics have been released about the three-hour show, but keeping the details quiet has been a challenge. A Twitter hashtag, #savethesurprise, was started by Olympic organizers to help keep details private, but some aspects of the show have leaked out nonetheless.

What the organizers have made public is that the show’s opening scene is dubbed “Green and Pleasant,” after a line from poet William Blake’s “Jerusalem,” and will showcase an idyllic view of a British countryside.

The elaborate set will comprise rolling hills, fields and rivers, complete with picnicking families, sport being played on a village green and real farmyard animals.

The torch will reappear during the show’s grand finale, when it will be carried into Olympic Stadium and used to set the Olympic cauldron aflame, symbolizing the beginning of the Games.

Fake ticket warning

Some Olympic competition commenced ahead of the official opening ceremony.

All 128 competing archers are taking part Friday in a preliminary round at Lord’s Cricket Ground to determine seedings for the individual and team competitions.

UK media reported Friday that hundreds of disappointed people had been turned away from the site Friday morning, however, after the apparent sale of some fake tickets and confusion over whether the event was open to the public.

The London organizing committee, LOCOG, said tickets had neither been advertised nor sold.

“We think we have made it very clear that this is not a free event, like the Road Races or Marathon which have been advertised as free events,” a statement said.

“This is a ranking round and there is no spectator access at all. We are dealing with this at the venue, along with some people who have turned up with fake tickets purchased from a fraudulent website.”

People are urged to “be extremely cautious and vigilant when attempting to buy tickets and only purchase from an official source,” the statement says.

Thursday saw the start of the men’s football competition, with global favorites Spain and Brazil playing, though not against each other.

Spain, which won the European Championship this year and the last World Cup, suffered a surprising 1-0 defeat to Japan in one of eight games scheduled Thursday.

Brazil — which, like Spain, is considered a likely contender to win Olympic gold — beat Egypt 3-2. Great Britain, playing football in the Olympics for the first time since 1960, scored a 1-1 draw in its match against Senegal after letting in a late goal.

Two notable absences are Argentina and the United States, neither of which qualified.

U.S. lawmakers remember Munich killings

Sixteen members of the U.S. House of Representatives held a moment of silence Thursday to honor the 11 Israeli athletes killed at the 1972 Munich Olympics and urged Olympic leaders to hold a similar moment of silence at Friday’s opening ceremony.

American Jewish leaders and the widow of one of the Israeli athletes have made a similar plea.

The International Olympic Committee says it will honor the slain athletes at a ceremony in September for the 40th anniversary, but so far, there are no plans for an official remembrance Friday.

The Israeli athletes were killed after eight Palestinian terrorists disguised in track suits broke into the Olympic Village in Munich, demanding the release of 200 Arab inmates from Israeli prisons.

By Heather Kelly

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