Local legends suggest the existence of a feudal order prior to the birth of the municipality of Pontremoli and the rise of the Malaspina. Most of the fortifications still visible in the villages of the Rossano valley date back to that period. In Piagna some buildings in the center of the town recall the existence of a castle, in fact in the archival documents we find the Lords of the “Castle” of Piagna mentioned more than once. The village of Castoglio is also interesting, perched on a hill overlooking the Teglia valley, with the noble Palazzo Mori.
Here every town has at least one fortified house or noble palace built on the remains of older fortifications. Some families, over the centuries, have enjoyed feudal privileges and have enriched themselves with trade and with the opening in many cases of “abusive” customs.
When the Municipality of Pontremoli (of which Zeri was a part until 1812) entered the Grand Duchy of Tuscany with the consequent establishment of important economic relations with the port of Livorno, the Via dei Monti lost its commercial function continuing to remain the only connection with the Genoese area up to the present day with the parallel via di “Genova”, still in the Zerasco area, which led to Sestri Levante.
In Chiesa, from the name of the temple dedicated to S. Medardo rebuilt at the end of the 19th century on a previous medieval building, the remains of Palazzo Schiavi are visible, which housed the international battalion founded by the English major Gordon Lett, a highly charismatic figure in the War of Liberation. In Pradalinara pass, the crossing point of the Via dei Monti or de Pontremolo, which overlooks the mountain range that divides the Rossano valley from the Val di Vara, the Val di Magra and the peaks of the Apennines, a monument commemorates the fighters of the various nationalities of the international battalion.
