During the Gilded Age, Rittenhouse Square was home to Philadelphia's high society, with more millionaires per square foot than any other American neighborhood except New York's Fifth Avenue. Established by William Penn in 1682 as the South-West Square and renamed after astronomer David Rittenhouse in 1825, Rittenhouse Square and its environs changed from an isolated district of brickyards and workers' shanties into the city's most elegant and elite...