Ornavasso borders the following municipalities: Anzola d'Ossola, Gravellona Toce, Mergozzo, Premosello Chiovenda. In the area there are two necropolises of the Lepontii-Celtic culture, dating to 2nd century BC – 1st century AD. From the 14th century to the late 19th century, Ornavasso and its frazione of Migiandone were a language island of Walser German, due to the presence of immigrants from the Simplon area.