Like in other Roman provinces, there are also in Britannia products which were not produced there, but had found their way to Britain by long distance trade. This trade was organised by the negotiatores Britanniciani.
Sometimes they indicated on inscriptions the goods they dealed with: salt and wine, pottery, glass and cloths. Parallel to these inscriptions we find not only pottery from South and Central Gaul in Britain but also Terra Sigillata and motto beakers made in Trier, Samian ware produced in the workshops of Rheinzabern and coarse ware from Mayen. Mayen in the Eifel region was also famous for its mill stones which were sold in many places in the western provinces.
All those places do not have access to the sea directly, but were situated along side the rivers Mosel and Rhine. In contrast to Trier and Mayen there was a natural barrier to go from Rheinzabern to the North Sea: the shallows near Bingen. For this reason, one finds less TS from Rheinzabern than from Trier north of these shallows.
Some Roman ship representations from Trier and the Rhine area belong in a civil context. They show two main typs - canoe shaped ones and vessels with flat bottoms. Both types are very small and could be handled by a small crew. Therefore those ships were suitable for civilian inland ship owners and traders very well.
The epigraphic evidence compared with the finds in Britain and the continental ship representations leds to the assumumption, that there were several steps of transportations.
At first the good were ships by small ships down the rivers up to river-mouth, where they were reloaded on big seagoing vessels. Certainly the sea trade lay in the hands of the negotiatores Britanniciani. Whether the nautae along the rivers transported such goods on their own accounts or by order of the negotiatores, as well, we do not know at the moment.