Cascadia

Cascadia is a bioregion of the Pacific Northwest defined by the watersheds of major rivers including the Columbia, the Fraser, the Snake, and the Klamath, stretching more than 2,500 miles from the Copper River in Alaska to Cape Mendocino in California and reaching east to the Yellowstone Caldera. It takes in all of Washington state, most of Idaho, and parts of Oregon, California, Nevada, Utah, Wyoming, Montana, Alaska, Yukon, and British Columbia, and contains roughly 75 distinct ecoregions. Unlike a political boundary, a bioregion like Cascadia is defined by natural characteristics, and its delineation is meant chiefly to serve environmental stewardship, reflecting the view that ecological and cultural boundaries should align with political ones. Within Cascadia, a densely populated corridor called the Cascadia Megaregion, running from Vancouver to Portland, holds more than 80 percent of the bioregion's population on only about 17 percent of its land area.