St. Louis is 11% larger than Pittsburgh.
Area: 153 km2 calculated
Pittsburgh is the seat of Allegheny County and with a population of 305,841 is the second-largest city in the U.S. state of Pennsylvania. With a metropolitan CSA population of 2,659,937, it is the largest in both the Ohio Valley and Appalachia and the 20th-largest in the U.S. Wikipedia
Area: 170 km2 calculated
St. Louis is an independent city and a major United States port in eastern Missouri. The city reaches the western banks of the Mississippi River, which forms Missouri's eastern border with Illinois. At the 2010 census, St. Wikipedia