The patron saint of Castel Vittorio is Saint Stephen, celebrated on 26 December. The parish church dedicated to him, whose current layout dates from the 1764 Baroque rebuilding, has a bas-relief of particular artistic interest, from the 16th or 17th century, on the side portal; inside is kept a painting depicting the Crucifixion of Jesus by the painter Marcello Venusti, datable to the second half of the 16th century, and a crucifix by Anton Maria Maragliano. On the right side of the building opens a portal topped by a small hanging portico from the 15th century.
The village, with its elliptical historic core, stands perched atop a steep hill, at the end of a slender wooded ridge overlooking the upper valley of the Nervia stream. Formerly called Castelfranco, it had numerous documented conflicts with the neighbouring town of Pigna, tied to the different political rulers administering the two towns, one aligned with Genoa and the other included among the holdings of the Duchy of Savoy: with the fall of Napoleon and the provisions of the 1814 Congress of Vienna, the municipality passed to the Kingdom of Sardinia, entering the district of Dolceacqua.
