The Araz (Arax) River once had its own mouth into the Caspian but now joins the 'nose' of the Kura. Until the early 19th century when it became the Russo-Persian border, its dramatic valley had for millennia been a major thoroughfare for armies, traders and holy-men. In his book Legend, archaeologist David Rohl disputes any claim Nakhchivan might have over the Noah legend, but makes up this for loss by identifying the river Araz as the Bible's 'River Gihon' - one of the four 'rivers of Eden'. He goes on to site the 'Garden of Eden' in Azerbaijan too, albeit in the southern half ie in what is now Iran.
If you're planning a trip to Azerbaijan you may be interested ▶ Azerbaijan highlights - For those who prefer to go unbeaten path, to explore less visited places and check national charisma of this small country in Southern Caucasus on the edge of Europe.