The Aqua Anio Vetus was an ancient Roman aqueduct, and the second oldest after the Aqua Appia. It was commissioned in 272 BC and funded by treasures seized after the victory against Pyrrhus of Epirus. The aqueduct acquired the nickname of 'old' (vetus) only when the Anio Novus was built almost three centuries later.
Three major restorations were done along with the Appia aqueduct: in 144 BC by the praetor Quintus Marcius Rex during construction of the Aqua Marcia by adding a secondary conduit in the Casal Morena area; in 33 BC when Agrippa took control of the entire water system of the city; and between 11 and 4 BC by Augustus. With this latter, an underground branch was built, theĀ specus Octavianus, which started from the current Pigneto area and followed the Via Casilina and reached the area where the Baths of Caracalla were later built.
Its construction was ambitious as it was four times as long as the Appia and its source much higher. It was clearly an engineering masterpiece, especially considering its early date and complexity of construction.
Sigmaringen Castle was first mentioned in the year 1077 in the chronicles of Petershausen monastery. The oldest parts of the castle are concealed beneath the alterations made during the 17th and the 19th centuries. The secret of the earliest settlement built on this defendable rock will never be fully revealed: large-scale excavation work would be necessary, which the extensive land development renders impossible. Judging from the many Roman remains unearthed in the area around Sigmaringen, the 12th century keep known as the 'Roman Tower' could be traced back to a Roman predecessor.
The castle remains that have been preserved (gate, great hall and keep) date back to the Staufer period around 1200. The castle remains were integrated into subsequent buildings. The foundations of the castle buildings are to a large extent identical to the surrounding castle wall.
These remains give us a good idea of how the castle might have looked during the 12th century.