Look at this!
View Larger Map
That gash of emerald green is the Chubut Valley in Patagonia, and Gaiman is one of the small Welsh-speaking towns near the Atlantic coast. When the Welsh got there in 1865 it was all desert (like the land around it still is now) but then, due to a woman called Hannah Jenkins, they managed to irrigate the narrow valley floor, and as a result grew bumper crops. I am astonished at how vividly this can be seen on google maps.