Prince of Wales Strait is situated in the Arctic Archipelago between the uplands of western Victoria Island and the east coast of Banks Island. About 275 km long and generally about 20 km wide, its depths reach 160 m at the southern end and become progressively shallower towards the northern entrance. The northeast-southwestern orientation prevents prevailing winds from driving heavy pack ice down the strait, which is primarily covered with locally formed ice that breaks up more readily, leaving a reasonably clear channel. Linking Viscount Melville Sound and Amundsen Gulf, the strait is one of 4 possible routes in the Northwest Passage and was first surveyed by a land party led by McClure in 1850, though it was not navigated until the RCMP patrol of Sgt Larsen in 1944. It has since become the preferred route of large vessels making the passage.