Pittsburgh is a large city in southwestern Pennsylvania. It is situated at the confluence of the Monongahela and Allegheny Rivers, which meet to form the Ohio River. Pittsburgh's triangular shape and steep hills have resulted in an unusual city design with a hodge-podge of neighborhood "pockets" with diverse ethnic and architectural heritage.
Pittsburgh has a rich history and an unusual array of cultural treasures for its size, owing mostly to the riches acquired by the city's booming steel industry of old.
Andrew Carnegie's United States Steel Corporation, which made him the richest man in the world, is still headquartered in Pittsburgh, as are several other major international corporations. The city's affluence has helped fund a world class museum, theaters, universities, and (of course) the Carnegie Library, which has branches in cities all across America.
Pittsburgh claims to have more bridges than any city in the world (only counting bridges over 20 feet high, there are 440 or so within Pittsburgh and over 1700 in the county), many of which are of quite unusual design and, of course, made of steel. The many locks and dams on the rivers still support extensive barge traffic.
Pittsburgh has always been a great melting pot, and today is home to thousands of foreign students attending universities such as Carnegie Mellon and the University of Pittsburgh.