 The valley is about 80 km in length by 20 km in width and lies at an altitude of about , with a population of over 200,000.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 (now Jayapura) found what the expedition called the ‘Grand Valley’.