Costigliole d'Asti – The Parish Church of San Siro in Bionzo

At the beginning of the 13th century, the village of Bionzo was confirmed by the Pope as one of the possessions of the Abbey of San Michele della Chiusa (Sacra di San Michele). In 1205, it passed to the noble Lanzavecchia family of Alessandria, and was later ceded to the municipality of Asti in 1288. In 1290, the castle and the village were destroyed by Marquis William of Monferrato and suffered further destruction in 1316. In 1567, the small church dedicated to Saint Syrus, the first bishop of Pavia, was described as being in fair condition, with a well-secured door and an intact roof. By 1605, it was noted that the walls were largely plastered and decorated. Since the end of the 16th century, the presence of a baptismal font had been documented, granted by religious authorities in Pavia. This made the church the seat of the parish of Costigliole until 1805, due to the distance from the main center of Costigliole. Around 1640, the old church was rebuilt, probably as a votive offering for surviving the plague of 1630–1632. The current sacred building was constructed between 1712 and 1721, replacing the 17th-century one which had become too small and was in poor condition. It was blessed—though not yet completed—on May 26, 1719, by a delegate of the Bishop of Pavia. The church has a simple yet elegant façade, marked by paired pilasters and crowned by a circular pediment. Noteworthy is a concrete statue of Saint Syrus above the single entrance portal, placed there in 1893. The bell tower, located on the right side, was raised in 1959 to accommodate a large clock. In 1927, a wrought-iron railing was added to the inner cornice (crafted by blacksmith Medardo Gozzelino). The interior decoration is the result of comprehensive restoration carried out between 1953 and 1955 at the request of the parish priest, Don Alessandro Paltro (1922–2007), executed by the Garbarino master builders of Costigliole. The painted decoration was done by Giovanni Gatti, under the direction of Carlo Frascaroli of Alessandria. The main altar, made of polychrome marble, was installed in 1953 by the Pallavicini company of Acqui Terme. On either side of the presbytery and on the choir wall are three frescoes painted in 1955 and signed by Francesco Mazzucchi (1896–1967), depicting the Last Supper (choir), Jesus and the Samaritan Woman (right), and the Calling of the Apostle Peter (left).