The Curse of Billy Penn (1987–2008) was an urban legend and popular explanation for the failure of major professional sports teams based in Philadelphia to win championships since the March 1987 construction of the One Liberty Place skyscraper, which exceeded the height of William Penn's statue atop Philadelphia City Hall. For decades prior to the construction of One Liberty Place, there had been a "gentlemen's agreement” in place ensuring that no building in Philadelphia would be approved that rose above the William Penn statue on City Hall.