The Mount Lofty Ranges zone covers an area of central South Australia bounded at the north by a line of latitude approximately in line with Crystal Brook, to the west by the Gulf St Vincent coastline and a line extending north from Port Wakefield, to the south by the line of latitude passing through Glenelg in the Adelaide metropolitan area and the portion of the Mount Lofty Ranges extending as far south as Mount Compass and bounded to the east by a line immediately west of the alignment of Murray river. The zone encloses the Barossa zone on all but its east side.