The statue is of William Penn (14 October 1644 – 30 July 1718) He was the son of the admiral and politician Sir William Penn. The younger Penn was a writer, early Quaker, and founder of the English North American colony the Province of Pennsylvania.

At 748 ft (167 m), including the statue of city founder William Penn atop its tower, Philadelphia City Hall was the tallest habitable building in the world from 1894 to 1908. It remained the tallest in Pennsylvania until it was surpassed in 1932 by the Gulf Tower in Pittsburgh. It was the tallest in Philadelphia until 1986 when the construction of One Liberty Place surpassed it, ending the informal gentlemen's agreement that had limited the height of buildings in the city to no higher than the Penn statue.

By 1682 William Penn had proved himself an influential scholar and theoretician in England. He desired, however, to establish a Quaker community in the new world. Penn then had to demonstrate the practical skills of a real estate promoter, city planner, and governor for his "Holy Experiment", the province of Pennsylvania. He is therefore honored in that location.

In 1976, Philadelphia City Hall was designated a National Historic Landmark.

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