Portland is the largest and most populous city in the U.S. state of Oregon and the seat of Multnomah County. It is a major port in the Willamette Valley region of the Pacific Northwest, at the confluence of the Willamette and Columbia rivers. Portland consistently ranks highly in quality of life in the United States. Its climate is marked by warm, dry summers and cool, rainy winters. This climate is ideal for growing roses, recognized as the world’s influential city of roses.