Breach at Cucca

The so-called breach at Cucca (Italian: rotta della Cucca) traditionally refers to a flood in the Veneto region of Italy that should have happened on October 17, 589 according to the chronicles of Paul the Deacon. The Adige river overflowed after a "deluge of water that is believed not to have happened after the time of Noah"; the flood caused great loss of lives, and destroyed part of the city walls of Verona as well as paths, roads and large part of the country in lower Veneto.

The tradition asserts that a breach opened in the banks of the Adige at Cucca, nowadays Veronella, about 35 km SE of Verona.

Contemporary historians think that the breach never really happened, and the tradition simply refers to the disasters due to the lack of maintainment of the streams that followed the fall of the Roman Empire. The Lombards did not repair the banks, and the waters of the Adige had been let free to flow through the lower Veneto for centuries, in order to set a swamp on the borders with the Exarchate of Ravenna.

This point of view should be balanced against the worldwide disastrous climate changes of 535-536. Even though the dates do not exactly align, it is a fact that in that century there was at least "one year without summer", it is conceivable that the exceptionally bad weather conditions reported worldwide for that unknown year, whose consequences included skipped harvests and famine in places as far apart as Ireland, Scandinavia and China, constitute the real background also for this reported climate disaster.

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Wikipedia