The Chapel of the Madonna del Dosso is located between the Baitana and Cantalupo farms, in the Gaggiano area and is a very small building, approximately 36 m2 with a portico on the front as wide as the chapel itself, approximately 2 meters deep and supported by two pillars. Under the portico two stone benches offer hikers the opportunity to sit so they can enjoy the silence and tranquility of the place. The access door is made of iron while on the sides there are two small windows closed by a security grille and a thick metal mesh. Two other windows are present in the side walls. Inside, in a central position on the wall in front of the entrance, the small altar is beautifully displayed above which a canvas reproduces the Annunciation while to the side there is a painting depicting a Madonna breastfeeding the Child
The year of construction of the Chapel is not certain, due to the lack of documents proving the exact date. Its known history starts from the 12th century, when Bonirola was called Iborino and was an independent locality made up of a few settlements and farms. Iborino takes its name from an ancient Celtic tribe, the Iborini, present in this area a few centuries before Christ and soon assimilated by the Insubre people. Already at the end of the 16th century there was a chapel called Madonna dei Borini