In the early 1640s, the Swedes built a blockhouse on a tributary to Darby Creek, which empties into the Delaware River. Its presumed location is in Philadelphia’s Kingsessing neighbourhood, near Cobbs Creek Parkway and Greenway Avenue. According to a report by Andries Hudde compiled in 1647 or, most likely, 1648, Nya Vasa must have been in existence earlier. In 1643, Printz reported of Upland and Schylenkyll (Schuylkill): “these two places are now open, yet strong wooden houses are built upon them with small stone-cannon.” Myers asserts that this “evidently” refers to “Wasa, or Nya Wasa, at Kingsessing.” He may well be right, although the first use of that name for the location comes from Acrelius, writing over a century later. According to Acrelius, this place, and some others, “which are marked upon the oldest maps, were places laid out and planned, but did not get established under the Swedish administration.” Despite this confusion, it is clear that a fortified house, later called Nya Vasa, was built in the early 1640s.