King of Prussia (also referred to as KOP)[4] is a census-designated place in Upper Merion Township in Montgomery County, Pennsylvania. As of the 2020 census, its population was 22,028. The community took its unusual name in the 18th century from a local tavern named the King of Prussia Inn, which was named after King Frederick the Great of Prussia. Like the rest of Montgomery County, King of Prussia continues to experience rapid development. One of the largest shopping malls in the United States, King of Prussia, is located here. Also located here is the headquarters of the Nuclear Regulatory Commission Region I. King of Prussia is considered to be an edge city of Philadelphia, consisting of large amounts of retail and office space situated at the convergence of four highways.