Mier was a local municipality in Northern Cape until August 2016, when it merged with //Khara Hais to form Dawid Kruiper Local Municipality.
Mier covered the dry Kalahari frontier west of the Orange River, bordering Namibia and Botswana. Its seat was Rietfontein, and its main settlements were Askham, Groot Mier, Noenieput, Philandersbron and Rietfontein, along the fringe of the Kgalagadi Transfrontier Park.
Mier’s population was small and scattered even by Northern Cape standards — a few thousand people spread across cattle posts, game farms and small service towns close to the Kgalagadi Transfrontier Park. Farming and cross-border tourism toward Botswana and Namibia were the area’s main economic activities before and after the merger.
The 2016 merger combined Mier’s sparsely populated western half with //Khara Hais’s Orange River irrigation land around Upington, giving the new Dawid Kruiper municipality both a farming river town and a Kalahari hinterland. These towns are now profiled under Dawid Kruiper Local Municipality, which covers the whole merged area.