page_title: Olona
section_title: The cartography
hierarchical_section_title: Olona / The cartography
caption_attribution_description: Italiano: Mappa dell'Ing. Raggi del Consorzio Fiume Olona riportante il territorio da Legnano a Parabiago lungo il fiume Olona anno 1772
context_page_description: The Olona is an Italian river belonging to the Po Basin, 71 kilometres long, that runs through the Province of Varese and Metropolitan City of Milan whose course is developed entirely in Lombardy.
  The river born at 548 m s.l.m. in the Fornaci della Riana locality at the Rasa of Varese, at the Sacro Monte di Varese, within the Campo dei Fiori regional park. After crossing the Valle Olona and crossing the Alto Milanese, the Olona reaches Rho where it pours part of its water into the Canale Scolmatore Nord Ovest. After passing Pero, the river enters in Milan, where, at the exit of its underground route, it flows into the Lambro Meridionale, that flows into the Lambro at Sant'Angelo Lodigiano, in the quartier of San Cristoforo ending its course. Along the way, the water system formed by the Olona and the Lambro Meridionale crosses or laps 45 towns receiving the water of 19 tributaries.
  The Olona is known for the waterfalls and caves of Valganna and for having been one of the most polluted rivers in Italy. The valley carved by the river, thanks to the system of water wheels that exploited the driving force originated by the water, was one of the cradles of Italian industrialization.
context_section_description: The oldest map representing the course of the Olona of which we have documented trace is dated 1608. On it are also marked the bridges and, with a good precision, the constructions along the river but not the zone of the sources and not the measures of the various properties.
  For the section of Olona that crosses Milan the current route appears, as already mentioned, in the general town plan of Beruto in 1884. With it, the route of the Darsena of Milan branch is also indicated. The Darsena branch, before crossing Via Vincenzo Foppa, crossed both Via Vepra, whose name recalls both Canale Vetra, and the ancient quartier of the same name, where, after the defeat with Federico Barbarossa and the destruction of the city (1162), they were exiled the Milanese of Porta Vercellina.
  Here, until the fifties of the 20th century, there was the last section of a non-canalized river with a tortuous course, as well as the last artisan agglomeration that used its water for dyeing plants and laboratories for the treatment of heavy fabrics.
  For the upstream section of Milan, the first map with a certain precision is a map drawn in 1763. This document illustrated the section from the sources to Gorla Minore. Later, another was drawn up in 1772 by the "conservator" of the river Giuseppe Verri and by the engineer Gaetano Raggi on behalf of the consorzio del fiume Olona. Besides the infrastructures, it also reports the canals and the locks, and therefore it is the first map endowed with a certain completeness. The richest in detail, among the oldest ones, is instead a map of 1789 which is the work of friar Mauro Fornari and Domenico Cagnoni.
  Among the papers of the 19th century, are to be mentioned the map drawn by the engineer Vittore Vezzosi in 1861, which also refers to some reliefs carried out on the river, and that of the engineer Eugenio Villoresi (1878), on which the areas irrigated by the Olona are traced in great detail. The latter, in fact, also reports the canals and the irrigation ditches originating from the river.
caption: Map of the engineer Gaetano Raggi of the Olona River Consortium, showing the territory from Legnano to Parabiago (1772)
exif: {}