BBC: Genesis 2:10-14
A river flowed out of Eden to water the garden, and there it divided and became four rivers. The name of the first is the Pishon. It is the one that flowed around the whole land of Havilah, where there is gold. And the gold of that land is good; bdellium and onyx stone are there. The name of the second river is the Gihon. It is the one that flowed around the whole land of Cush. And the name of the third river is the Tigris, which flows east of Assyria. And the fourth river is the Euphrates. - Genesis 2:10-14
The full understanding of this text is currently beyond me. The principle truth is that the land was flourishing in the blessings of God. Just as God's rebuke of the king of Tyre refers to the adornment of creation (Ezk 28:13), so here the adornment of creation for Adam is plainly seen. This bounty of God's grace is the location that Adam is to be placed (Gen 2:15).
*The Bible Blogging Commentary is a slow and simple treading of the Scriptures. No quotes from other theologians and no explicit Greek/Hebrew lessons.*