The 49th Parallel is a circle of latitude that is situated 49 degrees north of the equator. It serves as a significant boundary line between the United States and Canada, stretching from the Pacific Ocean in the west to the Atlantic Ocean in the east. This line was established in the Oregon Treaty of 1846, which resolved territorial disputes between the two countries. The 49th Parallel is notable for its geographical and political importance. It passes through several U.S. states, including Washington, Montana, and North Dakota, as well as Canadian provinces like British Columbia and Manitoba. This boundary has played a crucial role in shaping the relationship between the two nations.