Agogna

The provided text does not describe a castle named Agogna; rather, it details the Agogna, a 140-kilometer river located in northern Italy. Flowing through the regions of Piedmont and Lombardy, the river originates near Monte Mottarone between Lake Orta and Lake Maggiore at an elevation of approximately 1,000 meters. It travels south through the provinces of Verbano-Cusio-Ossola, Novara, and Pavia, passing notable towns such as Borgomanero, Cureggio, and Novara before joining the Po River near Mezzana Bigli. As a left-bank tributary of the Po, it drains a basin of nearly 1,000 square kilometers and plays a significant role in the local geography of the Lomellina area.

Historically, the river holds significance from the Napoleonic era, during which the Kingdom of Italy named a department after the Agogna, establishing Novara as its capital. While there is no fortress or architectural structure associated with the name in this text, the riverbanks are home to important natural reserves. Specific areas like L'Agogna Morta and the Oasi di Agognate are protected sites managed by environmental organizations, highlighting the region's ecological value rather than any military or residential architecture.

Consequently, no information regarding a construction year, architectural style, or current condition of a castle exists within the source material. The content exclusively focuses on the hydrological course, geographical subdivisions, and environmental conservation efforts related to the waterway. Any directory entry seeking details on a specific castle structure named Agogna would find no supporting evidence in this record, as the name refers strictly to the flowing stream and the historical administrative division derived from it.