A powerful earthquake, rated at VII (Very strong) on the Mercalli intensity scale, struck northern Italy and Germany on 3 January 1117. The epicentre of the first shock was near Verona, the city which suffered the most damage. The outer wall of the amphitheatre was partially felled, and the standing portion was damaged in a later earthquake of 1183. Many other churches, monasteries, and ancient monuments were destroyed or seriously damaged, eliminating much of Verona's early medieval architecture and providing space for a massive Romanesque rebuilding. After the first shock of 3 January, seismic activity persisted for months, striking on 12 January, 4 June, 1 July, 1 October, and 30 December.
The earthquake was not only felt in Verona but across northern Italy, from Cividale to Pavia, south to Pisa and north to Switzerland. Outside of Verona the most damaged areas were Milan, Bergamo, Brescia, Venice, Treviso, Modena, Parma, and Cremona. The main churches of Padua all suffered major damage. News of the earthquake reached Montecassino and Reims. The Milanese chronicler Landolfo Iuniore reported that the church synods needed to be carried out in the open air, due to the destruction. In Germany, damage was also extensive. The Michaelskirche in Bamberg, the abbey at Brauweiler, and buildings in Rottenburg am Neckar, Constance, Meersburg, and Fénis were all reported damaged.
Recent studies, however, suggest that it was not a major, single event on 3 January, but instead a series of powerful shocks in the areas of Verona (west Veneto) and Cremona (Lower Lombardy), which happened in a few days or even in a few hours. Other earthquakes may have hit as far south as Pisa (northwest Tuscany) and as north as Augsburg (southwest Bavaria), as distinct events, in the same days.