Excavation for the piers of the railway line running north-west of _Vesuvius_, led to the discovery of a stretch of a canal-aqueduct, with seven piers, forming part of the Roman Serino aqueduct. The construction phases until its ruin and subsequent abandonment were identified. The aqueduct was flanked by two beaten earth roads. The _terminus ante quem_ for its dating was represented, in the 5th century A.D., by the so-called Pollena eruption of _Vesuvius_, the accumulation of eruptive material covering the collapsed pilasters of its arches. Close by, the channel of the aqueduct (in correspondence with pier 39 of the railway line) was underground (to a height of 1.93 m and a width of 0.70 m), with _opus caementicium_ walls built abutting the terrain, and a vaulted covering, probably visible in antiquity, also in _opus caementicium_.