Columbia...........like in the letters DC..................is also a river.................Canada shares that area............

After a period of dormancy, Mazama became active again. Then, around 5700 BC, Mazama collapsed into itself during a tremendous volcanic eruption, losing 2,500 to 3,500 feet (760 to 1,070 m) in height. The eruption formed a large caldera that, depending on the prevailing climate, was filled in about 740 years, forming a beautiful lake with a deep blue hue, known today as Crater Lake.^[5]

The eruptive period that decapitated Mazama also laid waste to much of the greater Crater Lake area and deposited ash as far east as the northwest corner of what is nowYellowstone National Park, as far south as central Nevada, and as far north as southern British Columbia. It produced more than 150 times as much ash as the May 18, 1980 eruption of Mount St. Helens.