Lomazzo is a town and comune in the province of Como, in the Italian region of Lombardy. It is situated halfway between Como and Milan. The ancient historical center of the town was founded on the top of a hill situated in the valley on the right bank of Lura. The municipal territory contains a large portion of the Lura Park. Lomazzo received the title of Città (City) with a presidential decree on July 11, 2006. Lomazzo borders the following municipalities: Bregnano, Cadorago, Cirimido, Guanzate, Rovellasca, Rovello Porro, Turate

For more than one thousand years, the central street of Lomazzo has been the political and religious border that cut the town in two parts, from south to the north. The communal administration was divided as well, so the town of Lomazzo was governed separately by two municipalities: Lomazzo Comasco (parish of San Siro, also called Lomazzo di Sotto or, in dialect, Lumazz de Sott) and Lomazzo Milanese (parish of San Vito, also called Lomazzo di Sopra or Lumazz de Sura).

In the Middle Ages the border between the communes of Como and Milan already passed through Lomazzo. Still in the 16th century the custom duties were collected at the passage of Lomazzo border, for the feudal rights granted to the Carcano family by the Spaniards, who at the time controlled the Duchy of Milan.

The division of Lomazzo originated during the barbarian invasions. The Lombard people settled down near the existing inhabited nucleus, remaining separate from the existing community so they could practice their Arian religion. Probably, when they were converted to Catholicism, they maintained a separate church. The missionaries were sent from towns of the diocese of Milan, so the first community continued to be in the diocese of Como and the new community remained faithful to the diocese of Milan.

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