appointed Hermann Detzner to lead an expedition to survey the border between the British protectorate, called Papua, and the German territory and to survey and map the interior. Detzner was a military surveyor. The expedition set off along the Langimar-Watut divide, and travelled by raft down the Watut River to its junction with the Markham River, and on to the Lutheran Mission station at Gabmadzung (near the Lae Nadzab Airport). 1914–1918 On 4 August 1914, Britain declared war on Germany. As World War I spread to the Pacific, Australian troops invaded German New Guinea, taking the German barracks in Herbertshöhe (present day Kokopo) and forcing the defending German colonial troops to capitulate on 21 September after their defeat at Bita Paka. On 6 August 1914, residents of the Protectorate were notified by proclamation that a state of war existed between Germany, and England, France and Russia. During this time Detzner continued surveying and avoiding allied forces. On 11 November 1918, Detzner was advised that the war had ended and surrendered himself at Finschafen complete with sword and sun helmet. He was interned at Sydney and returned to Germany. 1920–1945 In 1918, Kaiser Wilhelmsland and the other territories that comprised German New Guinea (New Pomerania and the islands of the Bismarck Archipelago) were administered by the Commonwealth of Australia. Beginning in 1920, Australia, under a mandate from the League of Nations, governed the former German territory of New Guinea. It was administered under this mandate until the Japanese invasion in December 1941. Most of the territory of New Guinea, including the islands of Bougainville, and New Britain, was occupied by Japanese forces before recapture during the final months of the war in the Australian-American New Guinea campaign. Natural features Quaternary glaciers created much of the topography of Kaiser-Wilhelmsland. Recent studies suggest Mount Wilhelm held approximately of glacial ice. Further north, closer to the Equator, the glaciers left behind large rubble fields. The territory of Kaiser-Wilhelmsland was largely mountainous, with Mount Wilhelm the highest peak of the Hagan Range, which separated the protectorate from the British Papua. There are several major rivers, notably the Sepik River which drops from the Highlands and winds through lowland swamp plains to the north coast. The Markham River flows from the Finisterre Range and ends in the Huon Gulf. The Huon Peninsula, named for the French explorer Jean-Michel Huon de Kermadec, has raised beaches, usually created