In 1970, BB King recorded his classic album Live in Cook County Jail in the Chicago penal institution, and came away deeply moved by the experience. King subsequently performed numerous free prison concerts, and co-established the Foundation for the Advancement of Inmate Rehabilitation and Recreation.
The image above features BB King performing live at San Quentin prison in 1981; he is one of a number of famous performers to have recorded and played in prisons (Credit: Getty Images)