During a 2013 trip to South Africa, then-President Obama looks out the window from the cell where Nelson Mandela was once jailed on Robben Island. Obama is giving a major speech Tuesday. Wednesday would have been Mandela’s 100th birthday.

During a 2013 trip to South Africa, then-President Obama looks out the window from the cell where Nelson Mandela was once jailed on Robben Island. Obama is giving a major speech Tuesday. Wednesday would have been Mandela’s 100th birthday.