Amongst the defence works of the territory of Rignano, the most important is Torre all’Isola [1, 2], placed in the plain and near Arno. In spite of a recent restoration, the tower presents clear signs of medieval brickwork, small arches and corbels in the upper area  and it is made by stones of middle and small dimensions disposed in regular and parallel lines with corners well finished with big sandstone ashlars, also used for the string course frames and some windows decorations.
The tower coping is only partially preserved, as notable by the remaking of the section located under the ceiling, partly plastered and partly cemented, while other restoration works are identifiable in the remaking of some corbels in bricks and in the rebuilding of the fireplace and of some windows.
The still existing openings on the south façade are the result of recent works, while the little window on the western side, refined in sandstone, can be considered contemporary to the bricks, datable for type and workmanship, to the middle of the XIII century, although some elements, particularly those in pietra serena, can be referred with certainty to following interventions (XIV-XV centuries).
The rest of the structure proposes again some characteristics of the “house for ladies” of the 13-14th century: an internal yard surrounded by a brick curtain in stage with the tower, whereon there opens an entrance door and a series of body of factory, today plastered, leant against the original centre.
At the beginning of the 15th century, the “tower or fortalice called La Torre a Isola” was propriety of the Florentine Lorenzo di Totto Gualterotti.