The lower Hudson Valley cuts through the Appalachian zones of the eastern USA - USGS
The Hudson River valley runs more or less north to south down the eastern edge of New York State, cutting through a series of rock types including Triassic sandstones and redbeds in the south and much more ancient Precambriangneiss in the north (and east). In the Hudson Highlands, the river enters a fjord cut during previous ice ages. To the west lie the extensive Appalachian highlands. In the Tappan Zee region, the west side of the river has high cliffs produced by an erosion-resistant diabase; these cliffs range from 400–800 feet in height.
During the last ice age, the valley was filled by a large glacier that pushed down as far as Long Island. Near the end of the last ice age, the Great Lakes drained south down the Hudson River, from a large glacial lake called Lake Iroquois.Lake Ontario is the remnant of that Lake. Large sand deposits remain from where Lake Iroquois drained into the Hudson; these are now part of the Rome Sand Plains.
The first Dutch settlement was in the 1610s with the establishment of Fort Nassau, a trading post (factorij) south of modern-day Albany, with the purpose of exchanging European goods for beaver pelts. Fort Nassau was later replaced by Fort Orange. During the rest of the 17th century, the Hudson Valley formed the heart of the New Netherland colony operations, with the New Amsterdam settlement on Manhattan serving as a post for supplies and defense of the upriver operations.
The valley became one of the major regions of conflict during the American Revolution. Part of the early strategy of the British was to sever the colonies in two by maintaining control of the river.
Following the building of the Erie Canal, the area became an important industrial center. The canal opened the Hudson Valley and New York City to commerce with the Midwest and Great Lakes regions. However, in the mid 20th century, many of the industrial towns went into decline.
In the early 19th century, popularized by the stories of Washington Irving, the Hudson Valley gained a reputation as a somewhat gothic region inhabited by the remnants of the early days of the Dutch colonization of New York (see, e.g., The Legend of Sleepy Hollow). The area is associated with the Hudson River School, a group of American Romantic painters who worked from about 1830 to 1870.
The numerous factories that at one time lined the Hudson River poured garbage and industrial waste directly into the river. This pollution was not assessed in a comprehensive fashion until the 1970s. By that time, the largest company still operating factories in the area was General Electric, which became primarily responsible for cleaning the Hudson River. In 2009 dredging was started to remove contaminated sediments from the river bed and in 2010 General Electric agreed to finance and conduct a second dredging campaign at the Upper Hudson River between Fort Edward and Troy. These works will be supervised by the United States Environmental Protection Agency. Though the work is slow going, environmental advocacy groups have lent their voice to the problem of pollution. Scenic Hudson, Hudson River Sloop Clearwater, Hudson Riverkeeper, and the NRDC continue to push for more action from General Electric.
The Hudson Valley is divided into three regions: Lower, Middle, and Upper. The following is a list of the counties within the Hudson Valley sorted by region.
^"Grapes of the Hudson Valley". Hudson Valley Wine Magazine. Retrieved 2011-09-29. "The Hudson Valley’s beautiful river, shorelines and mountains have led some to call our valley ‘America’s Rhineland.’"