The Beagle Channel is about long and is about wide at its narrowest point. It extends from Nueva Island in the east to Darwin Sound and Cook Bay of the Pacific Ocean in the west. Some from its western end it divides into two branches, north and south of Gordon Island. The southwest branch between Hoste Island and Gordon Island enters Cook Bay. The northwest branch between Gordon Island and Isla Grande enters Darwin Sound connecting to the Pacific Ocean by the O'Brien Channel and the Ballenero Channel. The biggest settlement on the channel is Ushuaia in Argentina followed by Puerto Williams in Chile. These are two of the southernmost settlements of the world.