Among this cultured society Costanza d'Avalos was eminent for culture, and admirably qualified in every respect to make an invaluable protectress and friend to her youthful sister-in-law. The transplantation, indeed, of the infant Colonna from her native feudal castle to the Duchessa di Francavilla's home in Ischia, was a change so complete and so favourable, that it may be fairly supposed, that without it the young Roman girl would not have grown into the woman she did. [Sidenote: HER BETROTHAL.] For in truth Marino, little calculated, as it will be supposed, such a stronghold of the ever turbulent Colonna was at any time to afford the means and opportunity for intellectual culture, became shortly after the period of Vittoria's betrothal to the heir of the D'Avalos, wholly unfit to offer her even a safe home. Whether it continued to be the residence of Agnes, while her husband Fabrizio was fighting in Naples, and her daughter was under the care of the Duchessa di Francavilla in Ischia, has not been recorded. But we find that when Fabrizio had deserted the French king, and ranged himself on the side of Ferdinand of Naples, he was fully aware of the danger to which his castles would be exposed at the hands of the French troops as they passed through Rome on their way to or from Naples. To provide against this, he had essayed to place them in safety by consigning them as a deposit in trust to the Sacred College.[155] But Pope Borgia, deeming, probably, that he might find the means of possessing himself of some of the estates in question, refused to permit this, ordering that they should, instead, be delivered into his keeping. On this being refused, he ordered Marino to be levelled to the ground. And Guicciardini writes,[156] that the Colonna, having placed garrisons in Amelici and Rocca di Papa, two other of the family strongholds, abandoned all the rest of the possessions in the Roman States. It seems probable, therefore, that Agnes accompanied her husband and daughter to Naples. Subsequently the same historian relates,[157] that Marino was burned by order of Clement VII. in 1526. So that it must be supposed, that the order of Alexander for its utter destruction in 1501 was not wholly carried into execution.