The castle of Groppo San Pietro was erected in a key position to control the connexions to the step of the Linari and from the Emilia region. Probably built by the Estensi family, it was dominion of the Moregnano and then of the Malaspina. Obizzo of Filattiera and then his son Bernabò lead their sour fights against the Emperor. Almost unvincible, the castle had an enormous importance in the conflicts of the XIII century that determined the fates of Lunigiana. Unfortunately the unstable hill where it was builded have mined the stability of the ancient castle, whose rests are constituted from a quadrangular base of tower and traces of town-walls.

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The castles of Comano