THE RIVER TREBBIA The source of the river Trebbia is in the mountains of Liguria, about 30 km far from Genova; the river Trebbia flows into the river Po after a 110 km course across the whole Province of Piacenza. Due to the purity of its waters, mainly in its higher tract, in the summer time it is crowded with bathers; it is also very well known by canoeists coming from all over Europe.The upper part of the valley where the river flows is characterized by high mountains surrounded by pastures and woods (chestnut groves, oak and pine woods) where highly prized mushrooms grow, in the right season. Not to mention the outstanding, spectacular landscape, which hardly finds other matters of comparison among the Italian rivers. From the source to the mouth, the river Trebbia has several tributaries; the most important one is the river Aveto (whose source is in Mt Caucaso), followed by Boreca, Brugneto, Cassingheno, Bobbio, Dorba and Perino streams.
In Zerba territory there are numerous species typical of the Alps area flora, growing unspoilt in an intact habitat.