Coglasno ancient Greek historian Ptolemy ancient name of the Volga River — Ra. However, on closer acquaintance with the original, Ra — the name is not the Volga. So named Kama in the first copies off the map of Ptolemy, who, with some probability, dated XVI century (Ptolemy's original maps are not preserved). Map TYPVS ORBIS A PTOL. DESCRIPTVS, given the name of the main channel of the river — Rha fl. (River, for Ra). It also shows the unnamed western tributary, which is easily recognized with its own Volga tributary — Oka.
On another map, also officially considered to be a copy from the maps of Ptolemy, given the name of the Volga itself. TABVLA EVROPAE VIII (Sarmatia, the second part). River signed: F? S occidental Rha fl. (West for Ra).
Analyzing other maps include:
Map TABVLA ASIAE II, as well a river Ra. Moreover, the "Ra" is named as the Kama channel and main channel flow.
Map TABVLA ASIAE VII. Shows the river Ra, coinciding with the Kama River Daiks (modern Urals). Volga is not shown because it does not climbed on the map.
Finally map TYPVS ORBIS VNIVERSALIS river shows without any western tributary (Volga).
All maps are analyzed in the publication of "Geography of Ptolemy" Sebastian Munster presumably 1540.
All maps can easily be observed that the bed of the river Ra shown so that the upper reaches of its modern Wisher. Who knows, perhaps the name itself Visscher means "Above Ra", the upper Ra. Also suggests a name for all the land near the river Ra — Prirale or the Urals, which raises thoughts about the true etymology of the place name Urals.