Baliem Valley The Baliem Valley, also spelled Balim Valley and sometimes known as the Grand Valley, of the highlands of Western New Guinea, is occupied by the Dani people. The main town in the valley is Wamena. The valley is about 80 km in length by 20 km in width and lies at an altitude of about 1,600-1,700 m, with a population of 100,000. As far as the outside world was concerned, the discovery of the Baliem Valley and the unexpected presence of its large agricultural population was made by Richard Archbold’s third zoological expedition to New Guinea in 1938. On 21 June an aerial reconnaissance flight southwards from Hollandia found what the expedition called the ‘Grand Valley’. Since then the valley has gradually been opened up to a limited amount of tourism.