The main church is dedicated to Saint John the Baptist, the patron saint of Bossolasco.

The first news of the church dates back to 1327. We know that in 1464 it was rebuilt and expanded by the Marquis Manfredo Del Carretto, maintaining the internal organization with a single nave covered by cross vaults and with a modest façade with a small bell tower. Unfortunately, nothing remains of this church apart from the valuable bell tower built in cut stone erected between 1462 and 1464 as documented by pastoral visits and the date engraved on a pilaster strip in the left nave. Over the centuries, the church of Saint John the Baptist has undergone numerous renovations and modifications that have completely distorted its original characteristics: it was completely redone to expand its dimensions by eliminating the steps in front of the façade, the apse was replaced, the façade was rebuilt in an advanced position compared to the previous one and with the insertion of fragments of inscriptions and old coats of arms.

In 1737 the parish priest of Bossolasco Giovanni Benedetto Tarditi, a native of San Benedetto, had the church repaired and in the same year it was consecrated by Monsignor Vasco. A few years later Giovanni Giordano from Turin sent the reliquary and the relic of San Giovanni Battista as a gift.

In 1927, at the behest of the parish priest of Bossolasco Antonio Maiolo, the church was completely redone. The bell tower, which had remained unchanged over the centuries, was raised to be proportionate to the majesty of the new building, built entirely of stone. With the architect Mesturino, it was decided to maintain the Gothic-Lombard style and the double-hut façade was created.

The entrance to the church is protected by a portico on pillars and pseudo-Romanesque arches concluded by terracotta flames. In the internal part of the portico, some ancient sculpted stones from previous churches were inserted. The interior is characterized by three naves covered by richly decorated ribbed cross vaults. The frescoes in the presbytery and apse were created in the 1930s by the painter Ovidio Fonti in imitation of the 15th-century frescoes.

The cut stones used to build the church of San Giovanni come from the Belbo. They were collected in the bed of the stream near Luzzi. The stones were worked on site so much so that until the 1960s there were still numerous scraps of stone from the work. They were loaded onto carts pulled by oxen to be transported to the church under construction. On the San Benedetto side of the Belbo stream, a fountain was built to water the workers and animals. The date 1926 is engraved on one of the stones used to build the fountain.