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Where did the Cordilleran Ice Sheet form during the Pleistocene?

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Map showing the extent of the Laurentide, Cordilleran, and Greenland ice sheets during the Wisconsin glaciation, roughly 100,000 to 11,000 years ago. The Laurentide Ice Sheet covers most of present-day Canada and parts of the northern United States in light blue, the Cordilleran Ice Sheet covers the Pacific Northwest in teal, and the Greenland Ice Sheet is marked in purple. Modern international and state or provincial boundaries are outlined for reference. — Pleistocene Epoch Ice sheets during the Wisconsin glacial episode penetrated deep into North America.

During the Pleistocene Epoch, the Cordilleran Ice Sheet formed in the mountainous regions of western North America. It extended from western Alaska in the north to northern Washington in the south, spanning the area between the Pacific Ocean to the west and the Rocky Mountains to the east.12