Portland ( PORT-lənd) is the most populous city in the U.S. state of Oregon, located in the Pacific Northwest region. Situated close to northwest Oregon at the confluence of the Willamette and Columbia rivers, it is the county seat of Multnomah County, Oregon's most populous county. As of 2020, Portland's population was 652,503, making it the 27th most populous city in the United States, the sixth most populous on the West Coast, and the third most populous in the Pacific Northwest after Seattle and Vancouver. Approximately 2.5 million people live in the Portland metropolitan area, making it the 25th most populous in the United States. Almost half of Oregon's population resides within the Portland metro area.

Named after Portland, Maine, which is itself named after England's Isle of Portland, the Oregon settlement began to be populated near the end of the Oregon Trail in the 1840s. Its water access provided convenient transportation of goods, and the timber industry was a major force in the city's early economy. At the turn of the 20th century, the city had a reputation as one of the most dangerous port cities in the world, and was a hub for organized crime and racketeering; this reputation dissipated after its economy experienced an industrial boom during World War II, and it became known for its growing liberal and progressive political values from the 1960s onwards, earning it a reputation as a bastion of counterculture exemplified by the popular slogan "Keep Portland Weird". This aspect of the city has since been championed by organizations such as Weird Portland United and the comedy series Portlandia (2011–2018).

The city operates with a mayor–council government system, guided by a mayor and 12 city councilors, as well as Metro, the only directly elected metropolitan planning organization in the United States. Its climate is marked by warm, dry summers and cool, rainy winters. This climate is ideal for growing roses, and Portland has been called the "City of Roses" for over a century.