Robinson Crusoe Island is the largest of the three islands of the Juan FernÃ ndez archipelago , which belongs to Chile . Robinson Crusoe Island , formerly known as Juan Fernandez Island , MÃ s a Tierra ( Closer to land ) , or Aguas Buenas , is the largest island of the Chilean Juan FernÃ ndez archipelago , situated 674 kilometres west of South America in the South Pacific Ocean . The archipelago is made up of three islands , Robinson Crusoe , Alejandro Selkirk and the small Santa Clara .