Time line: The Best of the Royal Wedding - May 19 has finally arrived: today Prince Harry will marry his American bride Meghan Markle.

The royal couple will return to Windsor, near to where their famous engagement photos were taken, to exchange vows. 

Click to see the wedding preparations and updates as guests begin to arrive at St. George's Chapel, Windsor.

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Time line: Harry greets guests - On the evening before his wedding, Prince Harry stepped out with his best man Prince William to greet well-wishers in Windsor.

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Time line: Markle and mother arrive at hotel - Meghan Markle arrived at the Cliveden House Hotel with her mother Doria Ragland last night, after having tea with the Queen. Both mother and daughter stayed here overnight before the big day.

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Time line: security forces - Security forces were on patrol in the streets of Windsor earlier on the morning of the wedding.

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Time line: crowds gather - Crowds gathered along the streets in Windsor in anticipation.

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Time line: decoration - Photos were released of the interiors of St. George's Chapel earlier on the morning of the wedding. It was decorated with a stunning array of flowers, including white roses and peonies.

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Time line: Oprah is here! - Oprah Winfrey arrived along with other celebrities at St. George's Chapel, Windsor.

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Marching bands - Marching bands performed ahead of the bride and groom's arrival at St. George's Chapel.

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All the way from Norway - Norwegian royal fans were seen gathering along the Long Walk ahead of Windsor.

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Diana - A female fan held up a sign with a picture of the late Princess Diana on it.

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Guests mingle - Sir Elton John, David and Victoria Beckham, and David Furnish chatted ahead of the wedding ceremony.

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Bride leaves hotel - We captured a first glimpse of Meghan Markle and her mother Doria Ragland, as they left their hotel. Markle wore Queen Mary's diamond bandeau tiara, which was lent to her by the Queen.

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Wedding guests seated - Guests George Clooney, Amal Clooney, Silver Tree, Abraham Levy, Celine Khavarani, Markus Anderson, Janina Gavankar, and Jill Smoller gathered in St. George's Chapel.

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Guests - An overview of the guests gathered at St. George's Chapel, Windsor.

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Crowds in Windsor - Crowds along the Long Walk watched as the car carrying the bride traveled towards the chapel.

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On her way! - Meghan and her mother Doria Ragland waved to crowds as they were driven to St. George's Chapel.

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The Queen arrives - Her Majesty the Queen arrived with her husband Prince Philip at St. George's Chapel.

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Prince Philip - Prince Philip, who recently had a hip operation, looked in good spirits.

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Princess Eugenie - Princess Eugenie wore a pale colored dress with a much subtler piece of headgear than she wore to Prince William's wedding in 2011. She will wed her fiancé Jack Brooksbank in the same chapel later this year.

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Groom and best man - Prince William and Harry bowed their heads in St. George's Chapel, ahead of the bride's arrival.

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St. George's Chapel - Almost all the guests were ready and waiting inside St. George's Chapel at Windsor.

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Prince Charles and the Duchess of Cornwall - Prince Charles and the Duchess of Cornwall arrived at the chapel.

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Doria Ragland - Meghan's mother arrived at St. George's Chapel ahead of her daughter.

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Doria Ragland - Meghan's mother was greeted on arrival at the chapel.

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Bridesmaids - The Duchess of Cambridge rode to the chapel in the car with Princess Charlotte and other bridesmaids.

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Princess Charlotte - Princess Charlotte watched curiously out of the car as she made her way to St. George's chapel.

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Bridesmaids - The Duchess of Cambridge and Princess Charlotte (left) arrived with Jessica Mulroney, her daughter Ivy Mulroney and other little bridesmaids Florence van Cutsem, Remi Litt, Rylan Litt, and Zalie Warren.

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Charles and Camilla - The Duke and Duchess of Cornwall sat waiting inside St. George's Chapel.

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Arrival at the chapel - Meghan arrived at St. George's chapel and the world got a glimpse of her dress for the very first time.

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The dress - The bride looked at the crowds behind her, her face covered by the long veil.

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Bride - Markle's dress was designed by British Clare Waight, the first female Artistic designer at Givenchy.

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Dress - The dress was a simple and modern design which fitted the American royal bride beautifully. 

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Entrance - Meghan entered the chapel with two pageboys holding her train.

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Solo walk up the aisle - Markle looked poised as she walked up the first half of the isle on her own. Unfortunately her father, Thomas Markle, was unable to make it to the wedding.

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Arrival at the altar - Prince Charles walked Meghan up the second half of the aisle, before she joined her husband-to-be.

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Happy couple - Harry and Meghan couldn't keep their eyes off each other as they waited for the ceremony to begin.

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Bishop - The Most Rev Bishop Michael Curry of the Episcopal Church gave a stirring address to the congregation.

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The Queen - The Duke of Edinburgh and the Queen were seated at the front of the chapel. The monarch was dressed in a bright green and purple.

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Vows - The couple looked calm as they listened to Justin Welby, the Archbishop of Canterbury.

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Duke and Duchess of Cambridge - Kate and William exchanged glances during the ceremony.

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Exchange of vows - Harry and Meghan exchanged their vows while Justin Welby looked on.

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Exchange of rings - Harry and Meghan exchanged rings before becoming man and wife. Contrary to tradition, Prince Harry will wear a wedding ring.

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Leaving the church - The new Duke and Duchess of Sussex stepped out of the chapel as man and wife.

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Royal kiss - Harry and Meghan shared a kiss outside St. George's Chapel after their marriage.

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Kiss from behind - Meghan and Harry's iconic kiss as seen from inside St. George's Chapel.

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Carriage ride - Prince Harry and his newly-wedded wife waved to crowds as they rode through Windsor. 

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Procession - Congratulations to the happy royal couple!

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