Castel Bianco ( in Ligurian: Castregianco ) is a municipality with 326 inhabitants (as at 31 December 2012) in the Italian region of Liguria. Politically, it is located in the province of Savona.
Castel Bianco is situated in geologically rough Valle Pennavaire. The Monte Castell'Ermo located with its 1092 meters above sea level, on the border province of Imperia, is the most important natural monument in the immediate vicinity of the church. On the slopes of Monte Alpe ( 1056 meters ), the four main settlements Veravo, Colletta, Oresine and Vesallo. The latter was devastated by an earthquake in 1887.
Castel Bianco belongs to the Comunità Montana Ingauna and is about 60 kilometers from the provincial capital Savona.
According to the Italian classification with respect to seismic activity, the community of Zone 3 was assigned. This means that Castel Bianco is located in a seismically active zone little.
The municipality is classified under climate category E, as the number of degree days has a value of 2126. This means that in Italy legally regulated heating season is between October 15 and April 15 for each 14 hours a day