The flood history of Arno River: the exceptionality of the event on November 4th1966

The paper aims to describe the exceptional flood event occurred on November 4th 1966 in the Arno River basin in Tuscany (Italy), in the occasion of its 50th anniversary. The flood history of Arno River, with a particular attention to the last two millennia, is also reported. Particularly, a classification of the flood events occurred since the XII century, based on the procured damages, is described. Eight flood events have been defined as exceptional. The recent exceptional and more famous flood occurred on November 1966. The flood event is investigated in detail here, with reference to the meteorological causes that determined the exceptionality of the event. The results of a hydrological model are discussed in the conclusions to show the flood hydrograph and its peak flow at Firenze Uffizi urban cross section. The estimation of the economic damage suffered by the various districts of Arno river basin after the flood is also considered.