LAKE MCDONALD, Glacier National Park, Montana Lake McDonald is the largest lake in Glacier National Park. It is located at 48°35′N 113°55′W in Flathead County in the U.S. state of Montana. Lake McDonald is approximately 10 miles long, and over a mile wide and 472 feet deep, Filling a basin gouged out by Ice Age glaciers, Lake McDonald is a classic glacial feature. This long fjord-like lake is surrounded by mountains on the north, south, and east with the Continental Divide, 14 miles away. The mountains provide a spectacular backdrop for the lake and also act as a rain block. Much of the blocked precipitation ends up falling on the McDonald valley. The result is a mild, damp climate. Stands of western red cedar and hemlock flourish in the valley of Lake McDonald. The wildlife, viewing here can be spectacular, with species including bighorn sheep, mountain goat, elk, black bear, and whitetail and mule deer. One of the most striking feature of some of these lakes is the presence of a variety of colored rocks and pebbles just below the water surface and on the shores. The rocks range in color from dark red to maroon, and from green to blue. Colored pebbles are seen in abundance on the shores of Lake McDonald on the western side of the park. The dark-colored rocks found at the upper end of Lake McDonald, along McDonald Creek and around Trout Lake are the result of subjecting the red and green iron-rich rocks to heat and pressure. Lake McDonald lies at an elevation of 3,153 feet and is on the west side of the Continental Divide. Going-to-the-Sun Road parallels the lake along its southern shoreline. The surface area of the lake is 6,823 acres. The lake is home to numerous native species of trout, and other game fish. Catchable species include, but are not limited to - westslope cutthroat trout, rainbow trout, bull trout. Lake Superior whitefish, mountain whitefish, kokanee salmon, and suckers. Grizzly bears, black bear, moose, and mule deer are found in many places near the lake but are most common on the north shore. The lake is surrounded by a dense coniferous forest dominated by various species of spruce, fir, and larch. McDonald Creek flows into and drains from the lake, and empties into the Middle Fork Flathead River shortly after.