Here you can see a section of an early medieval long-distance water pipeline. It was found in the immediate vicinity in 2004. Scientifically, it was dated to the construction period of the imperial palace, i.e. to the end of the 8th century AD.
The long-distance water pipeline carried high-quality drinking water from the "Karlsquelle" spring area near Heidesheim via the Wackernheim valley to Nieder-Ingelheim, to Charlemagne's palace. This was done via a 6.8 km long canal, most of which ran underground. The construction, made of quarried limestone, arched over a 40 cm wide channel, which was sealed by a waterproof special mortar (opus signinum). It is easily recognisable by its red colouring at the bottom of the channel. One section of this conduit presumably led directly to a settling basin in the centre of the Palatinate ("basin of the long-distance water conduit"), another section ran in front of the outer façade of the semicircular building and could also be traced in the round towers in front of it on the outside. The structure followed the construction principle of Roman water pipes. It is of central importance in the rediscovery of ancient building culture in the early Middle Ages and is so far unique for this period. Its construction was not necessary: there were sufficient water resources in the area around the Palatinate. But it provided more high-quality and, moreover, flowing drinking water. It could be used for water buildings and fountains, for example, to demonstrate wealth and luxury.
By the way: Remains of a Roman water pipeline were found very close to the source area of the long-distance water pipeline. It could have served as a direct model here.
