Dubris, is now Dover.
It was used by the Romans as a port and has a significant number of Roman remains still exiting including the lighthouse and the Roman Painted House.
Dover was also the location of a Saxon Shore Fort.
There was also a naval base for the Roman fleet, the Classis Britannica, although the fleet was actually based in Portus Itius (Boulogne-sur-Mer).
see Wikipedia
see Roman Britain
see Dover Museum