The ceremony will take place at the castle's 15th Century St George's Chapel with the Dean of Windsor David Conner officiating.
Britain's Princess Eugenie arrives accompanied by her father Prince Andrew, Duke of York, at St George's Chapel for her wedding to Jack Brooksbank in Windsor Castle, Windsor, Britain October 12, 2018. See her stunning dress here!
Final preparations are being made in the English town of Windsor for Britain's second major royal wedding this year, this time involving Queen Elizabeth's granddaughter Princess Eugenie.
Only a few Halloween face masks feature Eugenie, though some shopkeepers say that will change in the hours ahead of her wedding.
Princess Eugenie then met Jack Brooksbank at the altar.
Afterward, the newlyweds plan a carriage ride through the streets of Windsor to give the public a chance to see them up close.
Eugenie and Jack Brooksbank are to marry Friday at St. George's Chapel, which is part of the castle complex.More news: Red Sox Or Astros In ALCS?
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In spite of choosing the same venue as her cousin Prince Harry's wedding to Meghan Markle in May, with numerous same common elements including inviting more than 1,000 charity workers invited to watch from the grounds of Windsor Castle, there was a more low-key atmosphere.
The American lifestyle channel TLC will cover the event for the U.S., with a special show called "Royal Wedding Live: Princess Eugenie". It is not clear if five-month-old Prince Louis, will attend, but Harry and Meghan are expected.
Another 1,200 members of the public selected by ballot will listen to a live broadcast in the castle grounds, and thousands are expected to watch from outside.
The bride's mother, Sarah Ferguson, has also taken up a seat in the church dressed in green, alongside her oldest daughter Princess Beatrice, who is also serving as her sister's maid-of-honour.
The whole wedding will be shown on a This Morning special.