In the southern part of the Valle Olona, where the river leaves the last waters from the Prealps in order to increase themselves in the plain, Castellanza extends that, in position of transit between the alpine plain and mountain passes, sin from the prehistory was the start point of civilization and cultures. The Olona river clearly divides it in two nucleus. Most ancient it is Castagnate, on the left side. Of it news around to the thousands is had and came unified to the village of Castellanza in the May of 1869 with R.D. of Vittorio Emanuele III. The river of was always life and wealth, with the numerous flour mills that set in action grinders, presses, sawmills.
The rich campaign of filari and bays, produced to cereals and potatoes; it came cultivated the screw and important was the silkworm breeding. Remarkable increment to this earth came given from the great artery of the Sempione and the pleasant locality will be remembered from Stendhal like an oasis of green with a limpid small river.

Industrialization in the Milan High has always made the accounts, from its beginnings in then, with the energetic problems. From the hydraulic energy that in origin favored the takeovers along the course of the Olona river were passed, in times succeeded to you, to the energy of the vapor and, more ahead still, to that hydroelectric and thermoelectrial one. The problem of the relationship between progress of the industry and energy continuously remains opened.

The flour mills gradually lost their importance towards the end of the past century. The names had come in fact to open their factories long the river that will become famous in manufacturer-textile field: the Cantoni, Tosi, the Turati, the Cerini. In the high part in 1886 Luigi Pomini had opened its mechanical workshop, while other industries in the chemical field, electrical worker, placed side by side from handicraft laboratories, joined to first.

He was therefore that the men transformed themselves very soon in fact laborers, also continuing to carry out the agricultural activity. He was therefore for many until fifty years ago, while the primary activity came replaced from that secondary one. Castellanza has been developed along the distance of the S.S. 33 of the Sempione, following the perpendicular guideline regarding the river of the ancient roads that the peasants used in order to catch up the Olona. The next development has it capacity to melt itself with the centers of Legnano and Busto compressed Arsizio remaining but within the tracings of the Freeway of Lagos, the Railroads North, the railway line Milan-Gallarate and Be them 527.

This situation has pushed the communal administration to a characterized recovery of the structures and the areas correspondents to functions already dismissed or that they will become such in the next few years. Castellanza is a concrete example of requalification of the existing city woven one: I re-use of the old building nuclei, the reutilization of the free areas are not only an active recovery of the historical testimonies of the city but above all one conversion of the city ground. Some constructed industrial buildings on the Olona, have become of communal property and a part of they already has been red-use to social scopes. Between all it detaches the structure of the Cantoni spinning, partte of which it has been restructured becoming center of the University Carl Cattaneo.