The Sandakan Death Marches were a series of forced marches in Borneo from Sandakan to Ranau which resulted in the deaths of more than 3,600 Indonesian civilian slave labourers and 2,400 Allied prisoners of war held captive by the Empire of Japan during the Pacific campaign of World War II at prison camps in North Borneo. By the end of the war, of all the prisoners who had been incarcerated at Sandakan and Ranau, only six Australians survived, all of whom had escaped. It is widely considered to be the single worst atrocity suffered by Australian servicemen during the Second World War.