The National Geographic genome website has maps showing the migration route of some human groups out of Africa and through, in some cases, the area around the Black Sea into Europe. 

I participated and on my maternal line, my haplogroup is J, denoting the Neolithic farmers who left the Middle East and moved into Europe about 10,000 years ago (possibly because of a drought). Their route was just west of the Caucasus  Mountains. 

By the way, the name "Iran" is related to "Aryan."