Born of gold fever, now Africa's economic heart — and where the continent-changing history is read: the transformative Apartheid Museum, Constitution Hill, and Vilakazi Street that housed two Nobel laureates. Family side: Gold Reef City (a theme park atop a real mine), the UNESCO Cradle of Humankind, lion parks; modern side: Sandton and Mandela Square, artistic Maboneng. Visit smartly: app rides always, organized township tours, Sandton/Rosebank hotels — two days complete any safari or Cape trip.