It is likely that the name “Rioni” is derived from the Svan language (word “rien” means “big river”).
With a total length of 327 kilometers, the Rioni is one of the largest rivers in South Caucasus (it is also the longest river wholly within the borders of Georgia).
It originates in the Caucasus Mountains in the region of Racha and flows west to the Black Sea, entering it north of the city of Poti.
The famed voyage of Jason and the Argonauts was said to have occurred by the Argonauts sailing up the river Phasis from its outlet of Black Sea to Colchis (modern Kutaisi in Georgia).
In the 1846 edition of the “Kavkaz calendar” (a yearly almanac on the Caucasus published from 1845 to 1916), it is asserted that this way occured in 1250 BC.