Which British city was known to the Romans as Magnus Portus?
Portus Adurni Portus Adurni Portus Adurni was a Roman fortress in the Roman province of Britannia situated at the north end of Portsmouth Harbour. Listed in the Notitia Dignitatum, it is generally accepted as having been located at adjoining Portchester in the English county of Hampshire and was later converted into a medieval castle known as Portchester Castle. It is the best preserved Roman fort north of the Alps. The name "Portus Adurni" appears only in the list of Saxon Shore forts in the 5th century "Notitia Dignitatum", and the name is usually identified with Portchester, although it has occasionally been identified
Portus Magnus, Algeria Portus Magnus, Algeria Portus Magnus was a Roman port in western Mauretania Caesariensis. It was located near Roman Portus Divinus and actual Oran (Algeria). "Portus Magnus, spatio appellatus, civium Romanorum oppidum. (the locality is called "Portus Magnus", a city of Roman citizens). Plinius" Portus Magnus (Great Harbour) was even named "Arsenaria" under the Roman Empire (the name is the one that can be seen in its former coat of arms). It has several Roman remains, mosaics, and artworks, which were deplaced to the museum of nearby Oran. During Roman times, the main exports from the area used to be grain