Casciago is a comune (municipality) in the Province of Varese in the Italian region Lombardy, located about 50 kilometres (31 mi) northwest of Milan and about 4 kilometres (2 mi) west of Varese. As of 31 December 2004, it had a population of 3,960 and an area of 4.0 square kilometres (1.5 sq mi).Casciago borders the following municipalities: Barasso, Gavirate, Luvinate, Varese.