The Mincio River has always been Mantua's main defence and, starting from the 13th century, the city was additionally protected by the Serraglio, a wide territory between the upper lake, the Mincio and Po rivers, and Osone Nuovo and Fossaviva canals. The area was controlled by a complex system of sewers, moats and towers and, in case of extreme necessity, could be flooded by the Mincio and Po water, thus surrounding Mantua with a further defence behind Lake Paiolo. A valuable natural stronghold and evidence of how water could be a unique defence, the Serraglio has been protagonist of all the wars in Mantua's history.
Further information