Delaware River

Not a single dam crosses the main stem of the Delaware River, the longest undammed river in the eastern United States. It forms at Hancock, New York, where its East and West branches meet, and flows 282 miles (454 km) to the head of Delaware Bay, or about 330 miles (530 km) counting the bay. It serves as a border for its whole length, dividing Pennsylvania from New York, New Jersey and Delaware. At the Delaware Water Gap it cuts straight through Kittatinny Ridge between walls of sandstone and quartzite.

The river carries a remarkable load of history and people. On the night of December 25, 1776, George Washington led his army across it to surprise the garrison at Trenton, the city where the river now becomes tidal. Below Trenton it is a working seaway lined by Philadelphia, Camden and Wilmington. Reservoirs on its upper branches supply roughly half of New York City's drinking water, though the city sits outside the basin. The Lenape, whose homeland it was, called it Lenapewihittuk. Long stretches of the upper and middle river are protected as National Wild and Scenic Rivers.

• Philadelphia
  The sixth-largest U.S. city, between two rivers flows through
• Delaware
  The First State, a low coastal sliver on the Atlantic located in
• New Jersey
  The Garden State, densely settled between two cities located in
• New York
  The Empire State, from Manhattan to the Adirondacks located in
• Pennsylvania
  The Keystone State, ridge-and-valley heart of Appalachia located in
• Susquehanna River
  Longest river on the East Coast, feeding half of Chesapeake Bay related