Melzo is a comune in the Province of Milan in the Italian region Lombardy, located about 20 kilometres east of Milan. As of 31 December 2004, i…Melzo is a comune in the Province of Milan in the Italian region Lombardy, located about 20 kilometres east of Milan. As of 31 December 2004, it had a population of 18,400 and an area of 9.7 square kilometres.