Under the Romans, trade and cultural exchange continued to flourish in the Passau settlement. As the Celts had done earlier, the new rulers used the rivers as transport routes for people, animals and cargo. They also expanded the existing network of overland routes. There is evidence that ships were loaded and unloaded in the area of Passau now known as the Römerplatz. Some traders probably also came here with wagons to sell their goods. A specific type of Roman pottery used as tableware, known as Terra Sigillata, was found to the west of the defensive ditches of the fort. This pottery was imported over a period of more than four centuries! Some fine examples are shown in the display case. You can also see where each piece was originally made. In the first and early second centuries AD, Terra Sigillata was imported from large pottery production centres in southern Gaul such as La Graufesenque and Banassac. Later, import routes shifted towards central Gaul and manufacturing centres such as Lezoux. During the second and third centuries, new pottery workshops in eastern Gaul and Upper Germania began to supply the forts and settlements on the frontier. The best known manufacturing centres include those at Rheinzabern in Upper Germany and Westerndorf in Raetia. Despite the logistical challenges caused by the political situation in late Antiquity, the Romans still managed to transport North African pottery across the Alps and to Passau. Other wares came all the way from the Argonne in northern France. Further imports included pots made of soapstone from Switzerland, as well as glazed ceramics from the Rhineland and other Roman provinces. A key find is the base of a container with coal tar still stuck to it. The tar was probably used for caulking - to seal the hulls of ships and make them watertight.