Portland ( PORT-lənd) is a port city and the most populous city in the U.S. state of Maine and the seat of Cumberland County. Portland's population was 68,408 in April 2020. The Greater Portland metropolitan area is home to over half a million people, the 104th-largest metropolitan area in the United States. Historically tied to commercial shipping, the marine economy, and light industry, Portland's economy in the 21st-century relies mostly on the service sector and tourism. The Old Port is a prominent neighborhood known for its nightlife and 19th-century architecture.