The correct answer is "the prison camp he was sent to in an effort to get rid of him."
The main setting of Aleksandr Solzhenitsyn's Gulag Archipelago was the prison camp he was sent to in an effort to get rid of him.
"The Gulag Archipelago" is a non-fictional text written by Russian writer Aleksandr Solzhenitsyn in 1958 and 1968. It has three volumes. In the books, the author describes the life of prisoners in the Communist forced labor camps better known as Gulag. The author uses testimonies, interviews, and reports to make more impact on the arguments. It is correct that the main setting of Aleksandr Solzhenitsyn's Gulag Archipelago was the prison camp he was sent to in an effort to get rid of him.