Roman Cambridge was probably called Camboritum, but this, like the majority of Roman place names in England, fell into disuse, and the earliest definite reference to the town in post-Roman times gives the name as Grantacaestir. This occurs in Bede's great _Ecclesiastical History_, concluded in A.D. 731, and the incident alluded to in connection with the Roman town throws a clear ray of light upon the ancient site in those unsettled times. It tells how Sexburgh, the abbess of Ely, needing a more permanent coffin for the remains of AEtheldryth, her predecessor in office, sent some of the brothers from the monastery to find such a coffin. Ely being without stone, and surrounded by waterways and marshes, they took a vessel and came in time to an abandoned city, "which, in the language of the English, is called Grantacaestir; and presently, near the city walls, they found a white marble coffin, most beautifully wrought, and neatly covered with a lid of the same sort of stone." That this carved marble sarcophagus was of Roman workmanship there seems no room to doubt, and Professor Skeat regards it as clear that this ruined town, with its walls and its Roman remains, was the same place as the Caer-grant mentioned by the historian, Nennius. In course of time the Anglo-Saxon people of the district must have overcome their prejudices against living in what had been a Roman city, and Grantacaestir arose out of the ruins of its former greatness. In the ninth century a permanent bridge was built, and the town began to be known as Grantabrycg, or, as the Anglo-Saxon Chronicle gives it, Grantebrycge. Domesday toned this down to Grentebrige, and that was the name of Cambridge when a Norman castle stood beside the grass-grown mound which is all that remains to-day of the Saxon fortress. What caused the change from G to C is hard to discover, but when King John was on the throne the name was written Cantebrige, and the "m" put in its appearance in the earlier half of the fifteenth century, the "t" being discarded at the same period. It seems that the name of the river was arrived at by the same process. Perhaps the oddest feature of the whole of these vicissitudes in nomenclature is the similarity between the Roman Camboritum and Cambridge, for the two names have, as has been shown, no connection whatsoever.