Only the lovely faĆ§ade and double arcade portico remain of the ancient abbey fortress of S.Bartolomeo, founded by Bernardo di Liuno in 962. The lintel and architrave of the rectangular portal are decorated with a sculpted band of foliage volutes that enclose a fantastically rich bestiary whose style and theme are reminiscent of the technique of Maestro Acuto.
Of the Gothic bell tower only the base remains, whilst the bell gable is a Burgundian addition.
The interior has a nave and two aisles, cadenced by lancet arches on support pillars. The presbytery, comprising a single, square apse transept, is characterised by polystyle pillars that support ogival cross vaults.
The left hand nave leads down to the triple apse crypt and to a single, ancient chamber used as a sepulchral cell.