British Columbia (BC) is the westernmost province in Canada, between the Pacific Ocean and the Rocky Mountains. With an estimated population of 5.1 million as of 2020, it is Canada's third-most populous province. British Columbia is bordered to the west by the Pacific Ocean and the American state of Alaska, to the north by Yukon and the Northwest Territories, to the east by the province of Alberta, and to the south by the American states of Washington, Idaho, and Montana.

Alaska is a U.S. state on the northwest extremity of the country's West Coast, just across the Bering Strait from Asia. An exclave of the U.S., it borders the Canadian province of British Columbia and territory of Yukon to the east and southeast and has a maritime border with Russia's Chukotka Autonomous Okrug to the west. Alaska is by far the largest U.S. state by area, comprising more total area than the next three largest states Texas, California, and Montana combined, and the seventh-largest subnational division in the world.