New Castle

New Castle County covers the northern third of Delaware, the most densely populated stretch of the state and the only piece that breaks out of the coastal plain. The terrain rises from sea level on the Delaware River up into the Piedmont foothills along the Pennsylvania line — rolling hardwood country with stone outcrops along the Brandywine, a sharp contrast to the flat farmland of central and southern Delaware. Wilmington, the state’s largest city, anchors the urban core; Newark holds the University of Delaware; New Castle (the original colonial capital) and Middletown anchor the southern stretch. The Brandywine and Delaware rivers run through the county; the Hagley Museum, Winterthur, Nemours Estate, and the Delaware Art Museum cluster along the Brandywine on what were once du Pont family estates. Most trips center on the Brandywine corridor. The du Pont mansion-and-garden circuit (Winterthur, Nemours, Longwood Gardens just over the Pennsylvania line) supplies a multi-day itinerary; Wilmington’s Riverfront and the Delaware Children’s Museum carry the urban half; New Castle’s colonial cobblestones and historic district handle a short morning. Easy access from Philadelphia and Baltimore keeps weekends moving.