The Encyclopedia Americana (1920)/Hay River

HAY RIVER, a stream which rises in the Rocky Mountains in Athabasca, Canada, and flows northeast into Great Slave Lake. It is navigable for about 140 miles from its mouth; its entire length is about 360 miles. The two Alexandra Falls (named after Princess Alexandra, now Queen Alexandra of England) are found in the upper course; they average about 250 feet in height and 900 feet in width.