Where was Mandela imprisoned?

Primarily at Robben Island, off the coast of Cape Town, from 1964 to 1982 — 18 years. He was then transferred to Pollsmoor Prison (1982-1988) and Victor Verster Prison (1988-1990). He was released from Victor Verster on February 11, 1990.

What were conditions like at Robben Island?

Harsh. Mandela and other political prisoners did hard labor in a limestone quarry. The lime damaged his eyes permanently (he was sensitive to bright light for the rest of his life). Cells were tiny, damp, and cold. For the first several years, prisoners were denied news, limited to one letter every six months, and allowed one 30-minute visit per year.

How did Mandela maintain his mental state?

Several strategies: he exercised rigorously every morning (he maintained this discipline into his 90s). He studied law and earned his degree. He taught and debated with fellow prisoners — Robben Island was informally called "Mandela University" because of the discussions he facilitated. He maintained dignity in every interaction with guards, not as performance but as principle.

What did he read and study?

Law, history, philosophy, and philosophy of history. He was permitted limited books. He described reading as both escape and strategic education — understanding history of liberation movements elsewhere, understanding how power works, understanding what negotiations require.

What came out of the prison years?

A man significantly more strategic and more patient than the one who went in. Younger Mandela had been a militant who'd helped found the ANC's armed wing (Umkhonto we Sizwe — "Spear of the Nation"). The man who left Robben Island understood that armed struggle was one tool among many, and that the endgame required negotiation, reconciliation, and the ability to hold a fractured country together.