PIONA. - An ancient abbey in the diocese of Como, situated on a promontory almost at the mouth of the Adda.
It was a Cluniac abbey in the 12th century, and later passed into commendam. The church was dedicated in 1138 by Ardizzone, bishop of Como, to the most holy Virgin Mary and was therefore called S. Maria di P.; later, to S. Niccolò. Traces of frescoes remain in the apse; at the base of the holy-water stoup are two lions that formed part of the ancient ambo. Of the original bell tower, the base remains, while the upper part dates from 1700; adjoining it is the cloister with a quadrangular portico and small columns with artistic capitals. It was commissioned between 1252 and 1257 by Prior Bonaccorso da Canova di Gravedona, as indicated by two inscriptions. Behind the apse there remain ruins of a pre-existing oratory, believed by some to have been dedicated to the most holy Virgin, by others to the martyr s. Giustina. Everything was secularized by the French Revolution under the law of 8 May 1798, with the exception of the church and cloister, which were nevertheless abandoned in 1861 and restored only from 1906 to 1909. Since 1938 Cistercian monks sent from Casamari have resided there.