I believe this neat structure, like the one in the previous post, was a working part of an historic farm.
Farm Structure, Wilkinson County
Vanishing Georgia: Photographs by Brian Brown
Since 2008. A visual survey of Georgia's historic architecture and culture. 8,000 locations. 27,000 images.
Vanishing Georgia: Photographs by Brian Brown 
Are those stone blocks or early form of concrete blocks?
John, they are a “sculptural” form of early block, very popular in the early 20th century. Many communities, including my hometown of Fitzgerald, had factories that produced these by the tens of thousands. The blocks were often identified as “granitoid”.