The Pacific Northwest & The Columbia River Basin
The Pacific Northwest can be briefly described as the region
drained by the Columbia/Snake River system. There is no universal agreement
about how far beyond that core area the term is appropriate. Political
divisions pull the definition one way, physical geography another.
The Columbia rises in Canada, and so does the Fraser, whose
delta occupies the northern end of Washington’s Puget Sound country. The two
rivers follow the same notable pattern, flowing northwest along the Rocky
Mountain Trench before swinging abruptly south. (The trench continues unbroken
from Idaho to Alaska, the expression of long-term tectonic shifts affecting the
This map extends up to the headwaters of the Columbia above
Banff, east to the Continental Divide, south into northern Nevada for the
southern tributaries of the Snake, and into California for the southernmost
Included on the map: All of Washington, Oregon, and Idaho,
with lots of British Columbia, Alberta, and Montana.
Small - Scale is 1:2
million or 1" = about 32 miles
Large - Scale is 1:1.5
million or 1" = about 24 miles
map dimensions are approximate.