A root zone of the southern Appalachian master decollement is postulated to exist beneath Kings Mountain belt, on the basis of an alternative interpretation of COCORP seismic profiles, palin-spastic restoration of the entire crust, and earlier geological and geophysical interpretations. Mildly deformed Cambrian metased-imentary rocks beneath the decollement end beneath the Piedmont in the vicinity of Danielsville, Georgia. Reflections farther southeast are probably from ultramylonites. Weak subhorizontal reflections continue southeasterly to the Kings Mountain belt, where a series of east-dipping (30°) reflections dominate the section to a depth of 20 km beneath the Charlotte belt. Reflections southeast of the root zone are possibly all related to the structure in an accreted island arc.