The Tamesis River was a waterway on the island of Britannia on the planet Magna Roma.
History and specifics[]
During the Battle of Britannia, the river played an important part in trapping German tribesmen so that they could be crushed by Magna Roman soldiers. (TNG novel: The Captains' Honor)
- Given the parallel development of Magna Roma and Earth, this is the Magna Roman version of the River Thames.