Town in the province of Milan, Ossona is an important agricultural and industrial center and has, along with the nearby Casorezzo, ancient Roman origins. It is mentioned for the first time in a deed of 1213. Next to the parish church dedicated to St. Christopher, already mentioned in the list by Geoffrey Bussero (XIII century), other sites of interest are:
- The Church of San Bartolomeo, dating from the XI century, and erected by Archbishop Ariberto d'Intimiano, in order to provide a shelter for the archibishop militias that travelled through the area. It presents a XIX century façade in eclectic style, with Egyptian decorative elements, and within it preserves paintings of XVII-XVIII century paintings and an altarpiece attributed to Simone Pederzano, master of the famous artist Caravaggio;
- The Chapel of Lazzaretto, built in the XVII century in the immediate vicinity of where the military hospital was situated;
- Palazzo Litta-Modigliani, of the XVIII century;
- Villa Bosi, built by the Family in the XIX century.