Old Fort, Johannesburg (must see)

The Old Fort complex began in 1892 when a high-security prison was built to house white male prisoners. In 1896, Paul Kruger, then president of the South African Republic, decided to build a fort around this prison to protect the country from the threat of British invasion. In later years, the fort was also used as a prison. Ironically, it was at this place where the Boer military leaders of the Anglo-Boer War were imprisoned by the British.

The Old Fort prison complex was later extended to include "native" cells, called Section 4 and Section 5, and, in 1907, a women's section was added. An awaiting-trial block was constructed in the 1920s. Both political activists opposed to apartheid and common criminals were held at the prison. Mahatma Gandhi was imprisoned here in 1906, and striking white mineworkers in 1907, 1913 and 1922.

Under the apartheid government, only whites were held in the Old Fort itself, except for Nelson Mandela, who was given a bed in the hospital section when he was as an awaiting-trial prisoner in 1962 prior to the Rivonia Trial. Joe Slovo, Bram Fischer, Albert Luthuli, and Robert Sobukwe were also inmates. The site housed prisoners until 1983 when it was closed.

Nowadays the site hosts the Women's Gaol Museum, Number Four Museum, and the Old Fort Museum with exhibitions on history and human rights in South Africa.

Tips:
You can go into the cells, see and touch. There are signs everywhere in English to give you more information, as well as an orientation film to start. There is also an exhibition on Mandela and Gandhi.

Go for the guided tour. You'll get so much more out of it (and it's only a few dollars extra)!