With a population of over 400,000, Ndola is the third largest city in Zambia and the capital of Copperbelt Province. It has an international airport, one of three in Zambia (the others being Lusaka and Livingstone). Starting off ignominiously as a slave traders' settlement, Ndola became the centre of mining in Northern Rhodesia (pre-independent Zambia). It has since established itself as a prominent commercial and light industrial centre. Ndola lies just 10 km south-east of the DR Congo border.