This visualization shows a sequence of
-based data in the Pacific Northwest.
The Pacific Northwest (in the United States, commonly abbreviated as PNW), sometimes referred to as Cascadia, is a geographic region in western
North America bounded by the
Pacific Ocean to the west and (loosely) by the
Cascade Mountain Range on the east. Though no agreed boundary exists, a common conception includes the
U.S. states of
Washington and the
Canadian province of
British Columbia. Broader conceptions reach north into
Yukon, south into
northern California and east to the
Continental Divide, thus including
Western Montana, and western
Wyoming. Idaho, Wyoming, and Montana are more accurately termed the Inland Northwest (INW), as the climate, folia, fauna, and politic are different than in the Pacific Northwest, as well as a different time zone in all but North Idaho. Narrower conceptions may be limited to the
northwestern US or to the coastal areas west of the
Coast mountains. The variety of definitions can be attributed to partially overlapping commonalities of the region's history, geography, society, and other factors.
The Northwest Coast is the coastal region of the Pacific Northwest and the Northwest Plateau (also commonly known as "the
Interior" in British Columbia
 and the
Inland Empire in the United States) is the inland region. The term "Pacific Northwest" should not be confused with the
Northwest Territory (also known as the Great Northwest, a historical term in the United States) or the
Northwest Territories of
The region's largest metropolitan areas are
Greater Seattle, Washington, with 3.7 million people,
Greater Portland, Oregon, with 2.4 million people
Greater Vancouver, British Columbia, with 2.4 million people.
A key aspect of the Pacific Northwest is the
US–Canada international border, which the United States and the
United Kingdom established at a time when the region's inhabitants were composed mostly of
indigenous peoples. The border — in two sections, along the 49th parallel south of British Columbia and the Alaska Panhandle west of northern British Columbia — has had a powerful effect on the region. According to Canadian historian
Ken Coates, the border has not merely influenced the Pacific Northwest—rather, "the region's history and character have been determined by the boundary."