Portland-bound potash loads join the Columbia River at Wallula, Washington, a location which has long been a center of commerce. In the early 1800s this was the site of Fort Nez Percés, an important Hudson's Bay Company fur-trading post; now, it is the interchange point between UP and both the Palouse River & Coulee City's lines serving the Walla Walla area and a BNSF branch line from Pasco. Also located here are a large Boise Cascade paper mill and, in the distance beyond the mill complex, the Railex transload facility, where the then-weekly Produce Railexpress was preparing to depart.