In 1882 the Historical Society of Pennsylvania purchased a mansion at the corner of 13th and Locust streets. It soon became clear that the society needed a fireproof structure and more space to house its growing collection. In the early 1900s, the society constructed a new building on the property, designed by Addison Hutton. As part of the building’s 100th anniversary celebration, we invite the public to experience HSP as they never have before. Learn about the building and take a behind-the-scenes tour focused on the architectural history of HSP.