sentences:  The oldest female monarch at the time of her ascension was Mary I, aged 37 years, 151 days when she became queen in 1553.The oldest queen consort was Alexandra of Denmark, wife of Edward VII, who was aged when she became queen in 1901.If Camilla, Duchess of Cornwall, were to become Queen consort (or possibly Princess consort) today, she would be the oldest to do so at the age of .