It's just about this time of year when the evenings are especially long that I think of E.M. Forster's novel of Edwardian manners, A Room with a View. There's something utterly perfect in a lingering, early summer sunset over the Arno, as seen from your pensione. Although this card isn't dated, I think it's quite old. There's no message, but the original owner made notes in ink on the reverse as a record of a trip. (This was one of the original uses of postcards - as photos of one's vacation.)
Titled with "Cartolina Illustrata", the note offers a small glimpse of a memorable evening from an entirely anonymous hand... "Ponte Vecchio above which we saw the moon rise and cast its reflections on the Arno. The oldest bridge in Florence."
Maybe it was Lucy Honeychurch after all?