Erected in 1635 by order of the Viceroy of Alcalà based on a project by Cosimo Fanzago and executed with his sons Carlo and Cesare, it originally stood in Via Gusmana. The monumental marble structure features a Late-Mannerist triumphal arch. Dominating the center is the personification of the Sebeto River, the ancient waterway of Naples, depicted as a reclining old man pouring water from an amphora. On either side, two sea monsters spout water into the basins, while the top hosts historical coats of arms.