The Oglio (Italian:[ˈɔʎʎo]; Latin: Ollius or Olius; Lombard: Òi, Cremonese: Ùi) is a left-bank tributary of the river Po in Lombardy, Italy. It is 280 kilometres (170mi) long.
In the hierarchy of the Po's tributaries, with its 280 kilometres (170mi) of length, it occupies the 2nd place per length (after the river Adda), while it is the 4th per basin surface (after Tanaro, Adda and Ticino), and the 3rd per average discharge at the mouth (after Ticino and Adda).
Overview
The Oglio is formed from the confluence of two mountain streams, the Narcanello branch from the Presena Glacier, in the Adamello group and the Frigidolfo branch, in the Corno dei Tre Signori, part of the Stelvio National Park. The two streams that merge near Pezzo di Ponte di Legno have an average discharge of 1.5m3/s (53cuft/s).
The Frigidolfo branch, before merging with the Narcanello branch, receives the Arcanello branch, which have an average discharge of 0.5m3/s (18cuft/s), which receives a minor branch originating from Lake Ercavallo.
The Ogliolo stream, with an average discharge of 2.5m3/s (88cuft/s) and a length of 20 kilometres (12mi) (similar to the length of the main branch between the Frigidolfo-Narcanello merge at Ponte Di Legno and the Oglio-Ogliolo merge at Edolo) is sometimes considered a de facto fourth branch of the Oglio river.[citation needed]
It flows in a southwest direction, through Valcamonica and enters into the Lake Iseo at Costa Volpino. It leaves Lake Iseo at Sarnico and, after traveling a zone of moraine deposits, it joins the Po river at Torredoglio, not far from Cesole and Scorzarolo, in the province of Mantua. Its drainage basin, which corresponds to the region of Valle Camonica, covers 6,649 square kilometres (2,567mi2). It is part of the larger Po-Adige basin.[citation needed]
.jpg)
