Biblical narriation started not from Abraham or Ur, that is very much later (about 3000 years from the creation of man). Rather look at where the place of Eden was where unknown author (possibily) Enoch started to write some of the Genesis<quoted text>Ur is in Mesopotamia. Its shows that in the bible. Abraham then went to Haran which is an Assyrian city now Turkey. No one knows where Noah lived before the flood but its more than like he also lived in Mesopotamia.
And a river went out of Eden to water the garden; and from thence it was parted, and became into four heads.
11 The name of the first is Pison: that is it which compasseth the whole land of Hav'ilah, where there is gold;
12 and the gold of that land is good: there is bdellium and the onyx stone.
13 And the name of the second river is Gihon: the same is it that compasseth the whole land of Ethiopia.
14 And the name of the third river is Hid'dekel: that is it which goeth toward the east of Assyria. And the fourth river is Euphra'tes.
15 ¶ And the LORD God took the man, and put him into the garden of Eden to dress it and to keep it.
16 And the LORD God commanded the man, saying, Of every tree of the garden thou mayest freely eat:
Key words that you should note:
Havilah (son of Cush), Gold, Ethiopia, Ghion, Hiddekel, Assyria, etc