London (AP) - Wedding guests in elegant attire filed into Westminster Abbey and royal fans lined the streets of London by the thousands, hoping to snatch a glimpse of history as Prince William weds Kate Middleton in a marriage expected to revive Britain's beleaguered monarchy.
A third of the planet was forecast to be watching Friday as the future king and queen of England start their lives as husband and wife with the two simple words "I will," ending months of buildup and sealing their love with the most public of spectacles.
All the clamoring over every detail -- the wedding dress, her hair, her title, the romantic kiss on the Buckingham Palace balcony, the honeymoon -- finally will be answered. But the biggest question of all won't be answered for years: Is this one royal couple who will live happily ever after?
Will their union endure like that of William's grandparents -- Queen Elizabeth II and Prince Philip, now in its 64th year -- or crumble in a spectacular and mortifying fashion like that of his own parents, Prince Charles and Princess Diana?
Recent history augurs badly: The first marriages of three of the queen's four children ended in divorce. But the couple's chemistry brings confidence that this one will work.
William and Kate look fantastic together, seeming to glow with happiness in each other's company, and unlike Charles and Diana they've had eight years to figure out that they want to be together.
But the fate of their marriage will depend on private matters impossible for the public to gauge. A beautiful bridal gown, an eye-popping sapphire-and-diamond engagement ring do not guarantee a happy ending. Any wedding is fundamentally about two people. Will their lives together, starting with such high hopes, be blessed by good fortune, children, good health, productive work?
Much will depend on whether 28-year-old William and 29-year-old Kate can summon the things every couple needs to make a marriage work: patience, love, wit and wisdom. But they face pressures most of the world doesn't: the twin burdens of fame and scrutiny. Money, power, beauty -- it can all go wrong if not carefully nurtured.
These are the thorny issues upon which the fate of the monarchy rests, as the remarkable queen, now 85, inevitably ages and declines.
With just hours to go, dedicated royal watchers camped outside got an unexpected surprise -- a visit from Prince William. The groom-to-be emerged from his residence Thursday night to greet the hordes of well-wishers gathered along the processional route. Dressed in khakis and grinning broadly, William shook countless hands as his photo was snapped on cell phones and digital cameras.
By dawn on Friday, crowds were awake and waving flags for television cameras under steely gray skies and cool temperatures. Technicians ran last-minute checks on huge television screens broadcasting the ceremony at Trafalgar Square. Cheers erupted in Hyde Park when the television broadcasts began.
Brenda Mordic, 61, from Columbus, Georgia, clutched a Union Jack, with her friend Annette Adams, 66.
"We came for the excitement of everything," Mordic said. "We watched William grow up. I came for Prince Charles' wedding to Diana and I came for Princess Diana's funeral. We love royalty England and London."
Despite the forecast of scattered showers, the royal-couple to be will brave the elements and travel from the abbey to Buckingham Palace in an open-topped carriage. They will also have new titles -- the duke and duchess of Cambridge.
As royal wedding guests filed into the abbey, everything was set: The rehearsals have been held, the cakes have been baked, the toast of the best man (William's brother Harry) written, suits and uniforms pressed, hats carefully chosen, shoes buffed, flowers arranged and the champagne put on ice for two exclusive receptions at Buckingham Palace.
Hundreds of street parties are planned as Britons celebrate part of the heritage that makes them unique -- and overseas visitors come to witness traditions they've admired from afar.
"It's part of history," said Norene Shultis of Madison, Wis., who arrived in London Thursday after an overnight flight. "It's so different from the United States. We don't have royalty. And we think William and Kate will be a good couple and do lots of good things and live happily ever after."
The government has declared a national holiday, universally welcomed by schoolchildren, and there has been a marked proliferation of Union Jacks in the last week as London spruces up for the big event, which has drawn thousands of journalists and hundreds of thousands of visitors from overseas.
Some 1,900 immaculately dressed guests, including fellow royals from around the world, a smattering of pop stars, sports idols and dignitaries, will jam Westminster Abbey.
Though the designer of Middleton's dress remains a mystery, William surprised royal watchers with the announcement that he was wearing the scarlet tunic of an Irish Guards officer. His choice of ceremonial military dress sent a strong signal of his support for the armed forces, reinforcing his image as a dedicated military man and distancing him from past characterizations as a club-hopping party boy.
A number of famous people were left off the guest list, including President Barack Obama and Britain's last two prime ministers, Tony Blair and Gordon Brown, in a snub to their Labour Party, which traditionally is not as strong a backer of the monarchy as the ruling Conservatives. The invitation for Syria's ambassador was rescinded Thursday because of Britain's unhappiness with the bloody government crackdown there.
The wedding is expected to be watched by 2 billion people across the globe and draw a million well-wishers -- as well as some protesters -- into the historic environs surrounding Buckingham Palace, Westminster Abbey and other London landmarks.
The celebration will be British to the core, from the freshly polished horse-drawn carriages to the sausages and lager served at street parties. Some pubs were opening early, offering beer and English breakfasts -- sausages, beans, toast, fried eggs and bacon -- to wedding fans who wanted to watch it on TV with others.
The public festivities reflected Britons' continuing fascination with the royal family, which despite its foibles remains a powerful symbol of unity and pride.
"It's that mixture of the good-looking prince and the beautiful princess, but it's so much more than that," said Prime Minister David Cameron. "It's this institution that's helped bind the country together."
All this is set against a backdrop of intense public interest, simply because William is second in line to the British throne, born to be king.
The royals fervently hope that a joyous union will rub out the squalid memories of Prince Charles and Princess Diana embarrassing each other and the nation with accusations and confessions of adultery as their marriage slid toward divorce.
And there is no small irony in the sight of Americans waking up before dawn (East Coast) or staying up all night (West Coast) after their fellow countrymen fought so fiercely centuries ago to throw off the yoke of the British monarchy and proclaim a country in which all men are created equal.
"We have celebrities. Hollywood, that is kind of our royal family and it is not the same. We are just so happy for Will and Kate and having followed them from growing up, it's just very exciting," said Julie Lischer, an American tourist from Atlanta, Georgia.