The notion persists that by the time Philadelphia achieved political and economic prominence in the mid-eighteenth century, it was a “wholesome grid of streets and squares.” City maps perpetuated this myth when in fact the immediate needs of the new colony had precluded methodical building. From the start Philadelphians struggled to balance the demands of private entrepreneurship and public works within changing systems of land allocation and governance. Most important, William Penn never obtained a legal warrant to confirm that city government had jurisdiction over the squares. As settlement expanded, with no authority charged with their improvement, the squares became vague, marginalized spaces vulnerable to abuse. By the first decades of the nineteenth century, when the city finally responded to residents’ concerns about public health and the preservation of Penn’s legacy, Philadelphians faced the challenge of repairing landscapes that had never really existed. When at long last, Philadelphia’s city councils did take a direct hand in the systematic improvement of Penn’s squares, the city assumed a pioneering but still underappreciated role in the history of public park development in the United States.