Theirs will be the second wedding within the British royal family in the space of a year.
But Zara Phillips' union with Mike Tindall is already looking to be worlds apart from that of her cousin Prince William, to Kate Middleton.
For a start the wedding will be held in Edinburgh. The last royal wedding in Scotland was that of Princess Anne in 1992.
The 17th century Canongate Kirk will be a much more modest location than Westminster Abbey.
The church's website states wedding fees are £75 for the organist, £25 for the church officer and a minimum donation of £200 to the church.
The venue was originally booked for another couple but they agreed to move their nuptials so that the royal pair could marry there on July 30.
Edinburgh-based graphic designer Cherith Harrison said: "We received a phone call from the minister who'd asked would it be possible for us to consider moving to another venue as Zara and Mike were keen to get married there."
She added: "There was no money, cash incentive or anything like that. Out of goodwill, we were just happy to move for them."
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