Castelli di Cannero, one of a group of small islands in Lake Maggiore on which castles have been built. They are all that remains of the Rocca Vitaliana Fortress,
built between 1519 and 1521 by Ludovico Borromeo. The fortress was built over the ruins of an earlier castle, the Castello della Malpaga, which had been used since
the 15th century as a refuge by the cruel Mazzarditi family, which took control of the burgh of Cannobio between 1403 ans 1404, terrorizing the inhabitants with their
acts of violence and piracy. Eventually, the Viscontos laid siege to the fortress, starving the villains into surrender. The old castle was razed to the ground and
the Rocca Vitiliana built to defend the upper parts of Lake Maggiore from incursions by the Swiss. All that remains of the castle is a ruined tower and some crumbling walls.