At the northern end of a 65 mile fjord known as Glacier Bay are the U.S.-Canadian border and the stunning Margerie Glacier. This tidewater glacier flows 21 miles from the 12,860 foot Mount Root, which is part of the Fairweather Range, until its mile-wide terminus reaches the Tarr Inlet. This massive tower of blue ice stands about 250 feet above the waterline with another 100 feet below sea level.