The name says that the embankment began here. The Fossiones philistinae, the Adige embankment system that lay a little to the north, gave the place the name Caput aggeris, «head of the embankment»: from there Caputargilis, then Caodarzere in Venetian and Cavarzere in Italian. The castle, on the other hand, is gone: described as «a great and handsome fortress, furnished with arms and victuals», it was pulled down in the sixteenth century to make room for the cathedral and for the indispensable embankments on the river. On the town's arms it is still there, drawn in natural colours: a castle nobody has seen for five centuries.
In 1923 Cavarzere was to be divided between the provinces of Rovigo and Venice; the people protested and the plan was withdrawn, and the Province of Venice gave the comune a column topped by the Lion of Saint Mark, which looks towards Venice, to thank the citizens for their loyalty. Then came the two wounds. The bombing of the Second World War razed almost the whole town — on the embankment wall the bullet holes can still be seen, and the twin town is Cassino — and the flood of 1951 drove a great many people away, many of whom settled at Settimo Torinese, with which the comune is twinned for that reason too. The town hall is palazzo Barbiani, of 1892, and its bell tower, sixty-five metres high, is among the tallest in the Veneto.