While many may immediately turn to the likes of , Dubai or London when thinking about the richest cities in the world, several others can be found in .

Its richest city, often dubbed the "City of Gold", is found in and is home to the highest number of millionaires on the continent.

, located right on the southern tip of Africa, is an incredible 868 miles and a nearly 16-hour drive away from the country's capital, Cape Town.

It stands as the most populous city in South Africa, with an incredible 4.8 million people in the City of Johannesburg alone.

Of this impressive population, the city also boasts an incredible 12,800 , the highest on the continent, as well as 25 centi-millionaires (worth £100 million or more) and two billionaires.

Among its wealthiest inhabitants are and family, chairman of the Swiss-based luxury-goods company Richemont, with a fortune of £8.3 billion and Patrice Motsepe, a billionaire who made his fortune through mining.

Most of Johannesburg's wealth is concentrated in , an upscale area often described as "the richest square mile in Africa." It is home to luxury shopping centres, five-star hotels, and the Johannesburg Stock Exchange (JSE), Africa's largest stock market.

Johannesburg earned its nickname as the "City of Gold" back in the 1880s, when the discovery of under the Witwatersrand hills suddenly put it on the map. The subsequent gold rush attracted over 100,000 people in just ten years and transformed it into an economic powerhouse.

The city remains the economic and financial hub of South Africa, producing an impressive 16% of the country's GDP. As the mining resources dwindled, the city's manufacturing industries have now extended to banking, IT, real estate, transport and retail, among others.

Johannesburg also proudly holds the title of one of the in the world. It is home to an estimated six million trees, a figure which continues to grow yearly. Johannesburg Botanical Garden, located in the Emmarentia suburb, is a popular recreational park.

It also has one of the largest zoos in South Africa, Johannesburg Zoo, which is home to about 2,000 individuals and 320 species. The Lion Park natural reserve, meanwhile is home to 80 lions and various other game.

Johannesburg is also a popular hub. OR Tambo International Airport is Africa's biggest and busiest airport, facilitating over 21 million passengers a year.

Lanseria Airport in the northwest of the city is closer to Sandton and is used for commercial flights to , Port Elizabeth, Botswana and Sun City, a luxury resort and casino in the North West Province of South Africa.

Cape Town, South Africa's capital, claims second place for the highest number of millionaires at 7,400. However, it is , the capital of Egypt, that claims the top spot for the highest number of billionaires (four) and the most centi-millionares (30).