Fourteen years ago he bid farewell as a devastated adolescent mourner to his mum in this very spot.
On Friday Prince William was able to return to Westminster Abbey as the happiest man in the land, taking his beloved Catherine Middleton as his wife.
Within their service, the couple remembered William's mother Princess Diana several times.
Their choice of music included Guide me, O though great redeemer, which was sung at Diana's funeral 14 years ago and at the memorial service to mark the 10th anniversary of her death.
Kate walked up to the aisle to The Introit, which was used in Prince Charles and Diana's 1981 wedding. It was one of several pieces of music taken from William's parents' nuptials.
Carole Middleton even wore an outfit by Catherine Walker, the label founded by her favourite designer.
And later in the day Diana was remembered in the speeches. Harry said his mum would have been "proud" to witness the marriage of her son to "beautiful" Kate.
Meanwhile William - who gave Kate his mother's engagement ring - paid tribute to his late mother, commenting on "how much she would have liked to have been here".
Diana's friend Rosa Monckton told the Daily Mail she would have approved of his choice and the fact that he married for love.
"How delighted she would have been at the length, stamina and fidelity of her son’s courtship," she told the newspaper.
"William was secure enough in himself to be able to marry for love, and that is Diana’s greatest legacy."