The Aqueduct of Vanvitelli or Caroline Aqueduct is a 38 km aqueduct that supplied water to the Reggia di Caserta and the San Leucio complex from the foot of the Taburno massif and springs of the Fizzo Contrada, in the territory of Bucciano.
Mostly underground, the aqueduct is noted for its well-preserved, three-tier, 529-metre-long tufa-arched section bridging the Valle di Maddaloni between Monte Longano and Monte Garzano. This section was modelled after Roman arched aqueducts, is 55.8 metres high at its highest point, crosses what is now highway SP335 — and was designated a World Heritage Site in 1997.
Wikipedia https://en.wikipedia.org/wiki/Aqueduct_of_Vanvitelli
More information on UNESCO's website http://whc.unesco.org/en/list/549
Address Vicinale Durazzano, 81020, Italy
Coordinates 41°3'32.52" N 14°24'9.079" E