Downtown Pittsburgh, colloquially referred to as the Golden Triangle, and officially the Central Business District, is the urban downtown center of Pittsburgh, Pennsylvania, United States. It is located at the confluence of the Allegheny River and the Monongahela River whose joining forms the Ohio River. The triangle is bounded by the two rivers. The area features offices for major corporations such as PNC Bank, U.S. Steel, PPG, Bank of New York Mellon, Heinz, Federated Investors, and Alcoa.