Although some maps may make Maine look like it’s farther north, the northernmost part of the contiguous United States is actually Northwest Angle, Minnesota. The northward protrusion of this piece of land from the rest of the United States was due to an 18th-century mistake about geography. In 1783, when the Treaty of Paris concluded the American Revolutionary War, the United States and Great Britain agreed that the new U.S. border in that part of the continent would extend from the most northwestern corner of Lake of the Woods “on a due west course to the river Mississippi.” But the era’s mapmakers didn’t know that the source of the Mississippi River, Lake Itasca, was actually south of Lake of the Woods. The Anglo-American Convention of 1818 addressed the issue by re-drawing the border to run due south from the northwest corner of Lake of the Woods down to the 49th parallel and then west to the Pacific. North of both the 49th parallel and Lake of the Woods, Northwest Angle is cut off from the rest of the contiguous United States. Like Alaska, it can be reached only by driving through Canada or by crossing water.
The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’s Terra satellite took this picture on May 19, 2002. Just east of Manitoba, just south of Ontario, and just north of the lake, Northwest Angle contrasts sharply with the more populated portion of Minnesota south of the lake. In this false-color image, red indicates vegetation, and the vegetation in Northwest Angle—like nearby portions of Canada—appears lush. In contrast, south of the lake is a sharp-angled cityscape, with shades of white, gray, and beige. It shows only a few rectangular patches of red.
The Northwest Angle was settled by Ojibwa, or Chippewa, Indians in the late 18th century. Today, the Red Lake Indian Reservation comprises much of the area. According to an article on the Minnesota Public Radio Website, the Northwest Angle attracted attention in the late 1990s when some of its residents expressed a desire to secede from the United States and become part of Manitoba. The announcement resulted from frustration over border-crossing rules and differences in fishing regulations between the two countries.
NASA image created by Jesse Allen, Earth Observatory, using ASTER data provided courtesy of NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan
Meltwater from glaciers to the east and west drains into Lake Morari, a large lake that lies at an altitude of 4,521 meters (14,830 feet) on the Tibetan Plateau. A stream on the west side provides the lake’s main inflow. Mud from this river gives the light blue hues to the lake water. The well-formed alluvial fan (image center), built by sediment from the main inflow river, is the reason the lake has formed at this point in the valley.