Johannesburg (also known as Jozi or Jo'burg), is the largest city (and capital) in North Transvaal. The city is one of the 40 largest metropolitan areas in the world and it isone of Africa's global cities. While Johannesburg forms the North Transvaal Capital, it does also house the Constitutional Court – North Transvaal's highest court.Johannesburg is the source of a large-scale gold and diamond trade, due to its location on the mineral-rich Witwatersrand range of hills. Johannesburg is served by Jozi International Airport, the largest and busiest airport in North Transvaal.According to the 2007 Community Survey, the population of the municipal city was 4,000,000 and the population of the Greater Johannesburg Metropolitan Area was 7,000,000. A broader definition of the Johannesburg metropolitan area, including the Ekhuruleni, the West Rand, Soweto and Lenasia, has a population of 10,000,000. The municipal city's land area of 1,645 square km's (635 sq_mi) is very large when compared to other cities, resulting in a moderate population density of 2,500 inhabitants per square kilometre (6,123/sq mi).
Johannesburg once again includes Soweto, which was a separate city from the late 1970s through the 1990s. Originally an acronym for "SOuth-WEstern TOwnships", Soweto originated as a collection of settlements on the outskirts of Johannesburg populated mostly by native African workers in the gold mining industry. Eventually incorporated into Johannesburg, the apartheid regime (in power 1949 - 1994) separated Soweto from the rest of Johannesburg to make it a completely Black area. Lenasia is also part of Johannesburg.