The Carolino Aqueduct and the "Bridges"
One of the most extraordinary engineering feats in 18th-century Europe was the construction of the Acquedotto Carolino (the adjectival form in Italian of Carlo in reference to Charles III of Bourbon, monarch of the kingdom of Naples at the time), including the long "bridges" segment (photo, right) of that waterway across the Maddaloni valley about 5 miles from the modern town of Caserta. The aqueduct is also known as the “Vanvitelli Aqueduct” in honor of the architect and engineer responsible for its construction, Luigi Vanvitelli.
The purpose of the aqueduct was to provide water to the new royal palace of Charles III of Bourbon and to the surrounding areas—that is, the city of Caserta and the new experimental community of San Leucio, in anticipation that the new palace, when completed, would be the centerpiece for a new capital of the kingdom of Naples. (For various reasons, that "new capital" did not come to pass.) The waterway, as well, would serve mountain communities such as Sant'Agata dei Goti along the way as it wended down from the source, the Fizzo springs of Mt. Taburno near Bucciano not far from Benevento. The aqueduct, indeed, wound up providing flatlanders with water for irrigation and even feeding into and augmenting the flow in the Carmiggiano aqueduct, a main water source for the city of Naples, itself.
The aqueduct was 38 kilometers long and marked by 67 sampling and inspection stations. One of the remarkable features of the aqueduct was that it dropped only half a millimeter for each meter of length, providing a solid but calm flow. Much of the aqueduct was submerged, including the last stretch in the Briano hill right above the north end of the grounds of the royal palace itself, before the water dropped down to feed a spectacular series of cascading pools. Construction was started in March of 1753 when Charles III was on the throne; it was inaugurated on May 7 of 1762 in the presence of the new boy-king Ferdinand, his regent, Bernardo Tanucci, the architect, Vanvitelli, and a goodly number of skeptics who had said it couldn’t be done.
The most impressive construction along the whole length was bringing the aqueduct through Mt. Longano and over the Maddaloni valley and into (and then through) Mt. Garzano. The bridge over that valley turned out to be 529 meters long, at the time the longest in Europe; it was sustained by three rows of arches with, from bottom to top row, 19, 29 and 43 arches, respectively. The average height of the bridge as it crosses the valley is almost 60 meters. The water took four hours to flow from the source to the Briano hill and down into the fountains. The bridge is well preserved and is a major tourist attraction in the area.
update Mar 25, 2016 -
The adjacent photo shows the trial run of an LED light display arrayed such as to illuminate the aqueduct, arch by arch. They turned it on the other night for the first time and it looks fine. The goal is to keep it on at night and thus turn this attraction into a sort of "beacon in the night," this as part of a wider plan to emphasize the cultural importance of the entire Caserta palace, on the UNESCO list of World Heritage sites.