To the utter delight of well wishers, the 85-year-old aristocrat kicked off her shoes, hitching up her skirt to perform a Sevillana, a flamenco-style dance.
Watching indulgently was the groom Alfonso Diez.
If the new duke consort looked slightly concerned it's understandable.
He was by her side a few years ago when she had spinal surgery.
Not that Cayetana Fitz-James Stuart seemed to be thinking about that as the band Siempre Asi struck up a tune outside Dueñas Palace in Seville.
She was oblivious to the TV reporters asking questions, leaving Alfonso, 61, to provide the answers.
He steered his bride round to face the press, but the dancing continued.
And Cayetana – keen to return the affection shown by locals – threw her bouquet into the crowd.
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