Despite being one the largest rivers in the USA east of the Mississippi River, the Susquehanna River does not have many large cities on its banks. Binghamton, Wilkes-Barre, and Harrisburg are its most notable cities, but none of those cities could be classed as a "major city". I understand the course of the river's two branches runs through some pretty difficult terrain (the Appalachians), but I would think that the mouth of the river would be a very strategically-located spot for a city, especially during the early years of the Industrial Revolution where access to coal (which could be shipped from Coal Country via the Susquehanna all the way down through the Chesapeake Bay) was a major factor.
So my question is - why are there no major cities on this important river? Is the mouth of the river too close to the already-established city of Baltimore? Is the river unnavigable or otherwise unsuited for barge traffic? Am I overstating the importance of the Susquehanna (and thus the Chesapeake Bay) or overlooking some other aspect of why this river does not have any major cities?
As European explorers quickly discovered, the Susquehanna is perhaps the world’s longest non-navigable river. Large rocks and shoals begin to appear only a few miles in from the Chesapeake Bay. At high tide, ships could get as far as Port Deposit, but no further. A 1588 Spanish expedition sent from St. Augustine in search of the English colony at Roanoke found the river, but named it San Juan de las Peñas (St. John of the Rocks). In 1608, what we know as Smith’s Falls stopped any further exploration by English Capt. John Smith.
Along the East Coast, cities typically prospered at the “fall line,” which was both the limit of upstream navigation and the location of water power that could drive mills or other industry. Havre de Grace and Perryville, Maryland, were indeed both important small industrial cities of the 19th century, but always stood in the shadow of nearby Baltimore, Wilmington, and Philadelphia, which had superior harbors and water power resources.