In Presidio County, Archeologists Document the Ancient Architecture of Warfare Originally broadcast on January 21, 2021 By Andrew Stuart photograph by Chris Hillen. Center for Big Bend Studies Director Bryon Schroeder at left. At right, Nature Notes producer Drew Stuart crouches behind one of the stone “bastions” found atop mesas in southern Presidio County. Our region’s Native American legacy endures in communities and living cultural traditions – and in countless emblems and traces on the West Texas landscape: in images on cave walls and boulders; in pottery and shards of flint from stone-tool making; in the ashy remains of “earth ovens,” where agaves and sotols were cooked.