Sister cities of Allentown, Pennsylvania

Allentown (Pennsylvania Dutch: Allenschteddel) is a city located in Lehigh County, Pennsylvania, in the United States. It is Pennsylvania's third most populous city, after Philadelphia and Pittsburgh, and the 222nd largest city in the United States. As of the 2010 census, the city had a total population of 118,032 and is currently the fastest growing city in Pennsylvania. It is the largest city in the metropolitan area known as the Lehigh Valley, which had a population of 821,623 residents as of the 2010 U.S. Census. It is also the county seat of Lehigh County. In 2012, the city celebrated the 250th anniversary of its founding in 1762.