Which South African prison island held Nelson Mandela for most of his imprisonment?

Robben Island held Nelson Mandela for most of his imprisonment.

Mandela was imprisoned on Robben Island from 1964 until 1982, after receiving a life sentence at the Rivonia Trial. He was held there with other anti-apartheid activists, including Walter Sisulu, Govan Mbeki, and Ahmed Kathrada. Prisoners performed hard labor in a limestone quarry and faced strict restrictions on communication, reading, and political activity.

Mandela was transferred from Robben Island to Pollsmoor Prison in Cape Town in 1982, partly because authorities wanted to separate senior prisoners from younger activists. He later moved to Victor Verster Prison before his release on 11 February 1990. Robben Island became a UNESCO World Heritage Site in 1999 and is now a museum. It is distinct from Pollsmoor and Victor Verster, which were later locations in Mandela’s imprisonment.