Altoona is a city in south central Pennsylvania Blair County, Pennsylvania, United States. It is the principal city of the Altoona Metropolitan Statistical Area (MSA). The population was 46,320 at the time of the 2010 Census, making it the eleventh most populous city in Pennsylvania. The Altoona MSA includes all of Blair County and was recorded as having a population of 127,089 at the 2010 Census, around 100,000 of whom live within a 5-mile radius of the Altoona city center according to U.S. Census ZIP Code population data.