西北角（Northwest Angle）位处于明尼苏达州的伍兹湖县（Lake of the Woods County）北部，是美国除了阿拉斯加州以外唯一北纬49度（49th parallel）以北的地方。北纬49度是连续48州的北部边界线，从西岸沿着华盛顿州、爱达荷州、蒙大拿州、北达科塔州和部分明尼苏达州到西北角，而东岸最北的领土也少于北纬49度。

地图投影有时制造出缅因州超过北纬49度的视错，但在纬线成直线的地图上并不会造成类似视错。

像阿拉斯加州、华盛顿州罗伯茨岬（Point Roberts）和明尼苏达州Elm Point，西北角只能乘船或飞机从美国本土前往，或经加拿大进入。

The Northwest Angle, known simply as the Angle by locals, and coextensive with Angle Township, is a part of northern Lake of the Woods County, Minnesota. Except for minor surveying errors, it is the only place in the United States outside Alaska that is north of the 49th parallel, which forms the border with Canada from the Angle west to Washington State. It is one of only six non-island locations in the 48 contiguous states that are exclaves of the U.S. although not directly connected to them by land. At 49.22° north latitude, it is the northernmost township in Minnesota and the northernmost point in the lower 48 states. The unincorporated communities of Angle Inlet and Penasse are located in the Northwest Angle.