California was once the Mecca of gold mining, but today the region that produces the most gold in the world is in South Africa, near the city of Johannesburg.
This mining area produces about half of the world's gold, and some years production has been over 1,000 tonnes!
The largest group of mines in South Africa is called East Rand Mine, covering an area of 12,000 acres. The largest mine in this group has tunnels extending more than 4,000 kilometres.
