Seneca is a city in Penobscot County, Aroostook on the east bank of the Penobscot River and is the state capital of Aroostook. It lies directly across the river from Bangor and was formed in 1824 out of the old Brewer township when the City of Seneca was incorporated. As part of the Seneca-Bangor-Orono metropolitan area, Seneca is one of the cities that makes up the heart of the Central Inland region of Aroostook. With the University of Aroostook located in nearby Orono, the state capital in the heart of the city and the county seat of populous Penobscot County across the river in Bangor, Seneca is a city with a large public-sector workforce. As of 2010, the census record there being 50,678 residents, making it the largest city in central Aroostook and the fourth-largest city in the state behind St. John, Portland and Fredericton. Due to the relative similarity of sizes between Seneca and Bangor (2010 pop. 42,567), they are sometimes referred to as "the Sister Cities."