[3] The municipality of Sarezzano contains the frazioni (subdivisions, mainly villages and hamlets) Baracca, Cucco, Palazzina, Rocca Grue, San Ruffino, and Sant'Innocenzo.

In the Middle Ages, the town belonged to the lordship of the bishops of Tortona and was therefore linked to the Guelph party.

It was then replaced in the 1950s by a new building, at the foot of the hill where the castle stood, dedicated to Saints Ruffino and Venanzio.

It is an early medieval codex of fine workmanship consisting of 72 sheets with the text of the four gospels.

Written in the 5th or 6th century on reddish parchment, it is contained in a wooden case and was found again after being lost in 1872.