Near Patigno, in the locality called "Castello" there are trace of the walls of the ancient castle. The so called "Castrum Zirri" is today totally disappeared. In 1226 troops of Piacenza and the Malaspina besieged the castle without conquering it.
A legend tells that the the last Marquise Malaspina was killed by a gunshot. The father of a girl of the Osti family, against the "ius primae noctis".

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