The Palouse is a region of the northwestern United States, encompassing parts of southeastern Washington, north central Idaho and, in some definitions, extending south into northeast Oregon. It is a major agricultural area, primarily producing wheat and legumes. Situated about 160 miles (260 km) north of the Oregon Trail, the region experienced rapid growth in the late 19th century, and at one time, the population of the Palouse surpassed even that of the Puget Sound area as the most populous region of the state.