Oregon is a state located in the Pacific Northwest region of the Western United States. It is bordered to the west by the Pacific Ocean, which forms its primary western boundary.
The state's geographical borders are defined by several natural and surveyed landmarks. The Columbia River serves as much of the northern boundary with Washington, while the Snake River delineates a significant portion of the eastern border with Idaho. To the south, the 42° north parallel marks the boundary between Oregon and California and Nevada.