Markle will be baptised and confirmed for the wedding and intends to become a British citizen, Harry's spokesman Jason Knauf told reporters.
Knauf said Windsor, Queen Elizabeth II's weekend residence, was a "very special place" for Harry and that he and Markle had spent time there together.
He said the couple would be putting their personal stamp on their wedding day, adding: "They will be making sure it reflects who they are as a couple."
The two will be visiting the city of Nottingham in central England on Friday for their first trip together since announcing their engagement on Monday.
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