From my Free Web Book 'AncientCanalBuilders.com' The largest wide-array man made (or at least non natural) structure in the world is in fact an ancient terra formed systems of agricultural-aquaculture canals in Northwestern Botswana and Northeastern Namibia, north of the Kalahari Desert in Southern Africa. Obviously quite ancient, the canal systems no longer provide free flowing water throughout its 105,000 mile array, but many sections show obvious intention to provide cross sectional irrigation. These canals are too evenly spaced over too large an area to be any kind of natural formation. Based on entry and exit points, it is readily...