What is the main setting in the play, The Island, by Athol Fugard?

The play is set in South Africa, with the main setting being Robben Island, the prison.

While stage directions offer no specifically defined placement in time for the play's action, because it was first written and performed during the time of apartheid in South Africa (i.e. the late 1940's to the early 1990's, and more specifically in the mid-1970's), it is reasonable and / or logical to understand that that is the period in which the story is set. The physical situation of the characters and their moral arguments against the power and dominance of the State support this hypothesis.