The Rioni River begins on the slopes of the Main Caucasus mountain range and then flows south-west to the city of Poti, where it enters the Black Sea.
The river is 327 kilometres long, which makes it one of the largest rivers of Transcaucasia.
The name Rioni may derive from the Svan word ‘rien’ which means “big river”.
Another version connects the name to the Ancient Greek verb ‘rheo’, (to flow).
According to Herodotus (484 BC – 425 BC) the Rioni River is the boundary between Europe and Asia.
It is thought that the Argonauts sailed along the Rioni (known in antiquity as Phasis) in their quest for the Golden Fleece.