Here is an excerpt from an article titled “In Search of Eden”:
… Last week I wrote about the message of the Euphrates River. This week let us travel further on the river and see what we discover…
Well, as we move further up (or is it down?) the Euphrates we discover something seriously wrong. According to the Torah the Euphrates should lead us to the Garden of Eden. As we read in Genesis (2:10-14): “A river flowed out of Eden to water the garden. From there it divided and became four major rivers [heads]. The name of the first is Pishon… the name of the second is river is Gichon… the name of the third river is the Tigris which flows to the east of Assyria. The fourth river is the Euphrates.” According to the Talmud the river that ‘flowed out of Eden’ is the Euphrates, which waters ‘the garden,’ and then continues and divides into four (Bechorot 55b and in Tosfos).
But today, as we continue to travel on the Euphrates we find that at the city of Al-Qurnah (in southern Iraq) it does join the Tigris River to form the Shatt Al-‘Arab, which flows into the Persian Gulf. The other two rivers are not to be found, and neither is the Garden of Eden!
So, where did Eden disappear? We know that the first human beings, Adam and Eve, were placed in the Garden of Eden. But where exactly is the geographic location on the map of this cradle of civilization?
This precise question is posed in Chassidus. Rabbi Dov Ber (son of the Rabbi Schneur Zalman of Liadi) asks: “The Garden of Eden is a physical place on Earth. Why then don’t we find it on the map? Scientists have wondered where is its location; as much as they searched they cannot find its geographic location”?! [1]
The explanation he offers: The Garden of Eden is an ethereal state of being, which is an intermediary between the physical and the spiritual, between matter and spirit. For example: the taste of an apple, though the taste is within the physical apple, yet it does not occupy tangible space. Before Adam and Eve ate from the Tree of Knowledge their bodies were also on this ethereal state; once they ate from the tree, they became more ‘materialized’ and therefore could no longer remain in the spiritual state of the garden. The Garden of Eden therefore exists on Earth, yet we (with our material eyes) cannot see it on the map. Just like the vegetative properties in the soil cannot be seen on the map. [2]
Perhaps this can be associated with one of the theories offered by some scientists (including Dr. Juris Zarins, a professor from Southwest Missouri State University) that the location of Eden is now submerged beneath the mouth of the Persian Gulf. Using advances in satellite technology, the hypothesis is that the northern tip of the Persian Gulf (where the Tigris and Euphrates end) had once been a lush, fertile region. This area was located at the junction of four rivers: the Tigris (Chiddekel); the Euphrates; the Karun River in southwestern Iran, which according to this theory is the Biblical Gichon (see also Kesseth HaSofer); and the now-dry riverbed Rimah-Batin (also known as the Wadi Al-Batin), which is the Pishon.
Look at a map and you’ll see that the Karun River joins the Shatt Al-‘Arab at… Basra (yes, Basra, Who is this coming from Edom, with soiled garments from Basra), and they empty into the Persian Gulf altogether.
According to Chassidic thought waters of the sea reflect the ‘hidden worlds,’ and are a more sublime state of being than land. Perhaps one can say that after the sin of the Tree of Knowledge, the Garden of Eden became submerged under the waters of the Persian Gulf – a fitting place for the ethereal Garden of Eden. Eden is like a piece of heaven on earth.
For the record there are other theories. Josephus for instance identifies the Gichon and the Pishon as the Nile and the Gangus. There is also a theory that the Garden of Eden is in the mountains of eastern Turkey. [3]
It should also be noted that the Talmud clearly states that the Euphrates could have been altered by man (Berochot 59b. Shulchan Aruch Orach Chaim 228:2). Additionally, one can argue that the flow of the rivers was altered, even drastically, by the Great Flood.
The only thing that is certain is that we do not know the location of Eden and that the search for Eden goes on.
As you can see, he combines source-analysis with mysticism. The rest of the article is worthwhile, too.