The river then enters Connecticut, which it divides into two almost equal parts. It passes through rich farmland until it reaches the dams and rapids of Enfield Falls at Windsor Locks. Windsor Locks stands at the head of the tidewater navigation of the river just below the Enfield Dam. The town was settled very early because river cargoes had to be transferred by land around the rapids. Across from Windsor Locks is Warehouse Point where William Pynchon, back in 1636, established a warehouse for the cargoes awaiting transfer. The Farmington River joins the Connecticut at Windsor.
The Connecticut River forms a boundary of Hartford, the capital city of Connecticut, where constitutional government as we know it began in 1639 with the promulgation of the Fundamental Orders. After the historic towns of Wethersfield and Glastonbury, the river passes the Dinosaur State Park where over 1,000 prehistoric footprints can be seen in sedimentary sandstone and fossils. The footprints were discovered as recently as 1966 by a bulldozer operator during the construction of a state highway.
From Rocky Hill, the river is flanked by Cromwell, once known as Upper Houses, and Portland, the former site of important shipyards and brownstone quarries, before it reaches Middletown. Middletown is the home of Wesleyan University and many important industries. Here, the river takes a southeasterly turn through a narrow valley in the eastern upland, while the broad, fertile river valley extends from Middletown down to New Haven. In prehistoric times the river emptied into the sea at the present site of New Haven. Over the course of time the deposit of rocks and sandstone forced the waters to the east, thus cutting a new channel for the river through the eastern highlands from Middletown to the sound.
At the Haddams, the river is joined by the Salmon River and overlooked by the Connecticut Yankee Nuclear Plant. Wooded hillsides now line the river as it continues past East Haddam and Chester. The Chester-Hadlyme Ferry provides a five-minute crossing of the river, hardly time enough to appreciate the spectacular view up and down the river and the view of Gillette Castle, which stands 200 feet up on a high cliff in Hadlyme on the southernmost series called the Seven Sisters. The ferry has been in continual operation since 1769.
The river flows through lofty rock ledges and the heavily wooded hillsides of Lyme and Deep River. On the eastern bank is Hamburg Cove with its beautiful sheltered harbor. On the western bank is Essex, with its beautiful harbor, narrow streets, fine old houses, and maritime traditions which have given it a character and charm so often associated with the typical New England village. The Connecticut broadens into numerous coves and tidal marshlands, and finally flows into the Long Island Sound between Old Saybrook and Old Lyme. Connecticut has an extensive shoreline of some 250 miles, and none of it actually boarders on the Atlantic. The river flows into the sound some thirty miles west of Montauk Point, Long Island's eastern extremity.
The mouth of the Connecticut, as it is approached from the sound, is a broad estuary a mile in width, made shallow by a large sandbar; a wary navigator must confine his course to the narrow but well-marked channels on the western, or Old Saybrook, side. The sandbar so impeded river navigation by deep draft ships that no industrial development has ever occurred along the shores of the riveršs mouth. Thus, it has remained in its pristine state and, in this respect, is almost unique among the major rivers of the United States.