Question: The geography of New York City is characterized by its coastal position at the meeting of the the Atlantic Ocean and a river that is how many miles long?

Context paragraphs:
Geography of New York City: The geography of New York City is characterized by its coastal position at the meeting of the Hudson River and the Atlantic Ocean in a naturally sheltered harbor.  The city's geography, with its scarce availability of land, is a contributing factor in making it one of the most densely populated cities in the United States.  Environmental issues are chiefly concerned with managing this density, which also explains why New York is among the most energy efficient and least automobile-dependent cities in the United States.  The city's climate is temperate.

Long Island Sound: Long Island Sound is a tidal estuary of the Atlantic Ocean, lying between the eastern shores of Bronx County, New York City, southern Westchester County, and Connecticut to the north, and the North Shore of Long Island, to the south.  From east to west, the sound stretches 110 miles (177 km) from the East River in New York City, along the North Shore of Long Island, to Block Island Sound.  A mix of freshwater from tributaries and saltwater from the ocean, Long Island Sound is 21 miles (34 km) at its widest point and varies in depth from 65 to .

Geography of Manila: The geography of the City of Manila is characterized by its coastal position at the estuary of the Pasig River that flows to Manila Bay.  The city is located on a naturally protected harbor, regarded as one of the finest harbors in Asia.  The scarce availability of land is a contributing factor that makes Manila the densest populated city in the world.

Cedar Island, South Carolina: Cedar Island is a river island in the Santee River of South Carolina roughly ten miles long and two miles wide that separates the Santee into two distributaries, the North Santee and the South Santee, before the river empties into the Atlantic Ocean.

Geography of Lafayette, Louisiana: Lafayette, Louisiana is part of the Gulf Coastal Plain region of the United States and is located at Coordinates 30°12′50″N 92°01′46″W.  It has an elevation of 36 feet (11.0 m).  One of the physical characteristics of the geography include many streams that drain the parish.  The primary river that runs through the city is the Vermillion River (Louisiana).  This river was formed by the confluence of a few small bayous, stretches about 70 miles long, and drains into the Gulf of Mexico.  Most of Lafayette's landscape is urban; however its humid and subtropic climate during the summer allow it to house many species of birds, alligators, and fish.  The winter season is mild.  While Lafayette is situated in a geographic location that is overall relatively safe, the city is susceptible to flooding; hurricanes are also a common natural disaster.

Lower New York Bay: Lower New York Bay is a section of New York Bay south of the Narrows, the relatively narrow strait between the shores of Staten Island and Brooklyn.  The southern end of the bay opens directly to the Atlantic Ocean between two spits of land, Sandy Hook, New Jersey, and Rockaway, Queens, on Long Island.  The southern portion between Staten Island and New Jersey, at the mouth of the Raritan River, is named Raritan Bay.  The Hudson Canyon, the ancient riverbed of the Hudson River which existed during the last ice age when the ocean levels were lower, extends southeast from Lower New York Bay for hundreds of miles into the Atlantic Ocean.  The nearby part of the Atlantic Ocean between New Jersey and Long Island is the New York Bight.

Waccamaw River: The Waccamaw River is a river, approximately 140 miles (225 km) long, in southeastern North Carolina and eastern South Carolina in the United States.  It drains an area of approximately 1110 square miles (2886 km²) in the coastal plain along the eastern border between the two states into the Atlantic Ocean.  Along its upper course, it is a slow-moving, blackwater river surrounded by vast wetlands, passable only by shallow-draft watercraft such as canoe.  Along its lower course, it is lined by sandy banks and old plantation houses, providing an important navigation channel with a unique geography, flowing roughly parallel to the coast.

Delaware and Raritan Canal: The Delaware and Raritan Canal (D&R Canal) is a canal in central New Jersey, United States, built in the 1830s, that served to connect the Delaware River to the Raritan River.  It was intended as an efficient and reliable means of transportation of freight between Philadelphia and New York City, especially coal from the anthracite fields in eastern Pennsylvania.  Before the advent of the railroads, the canal allowed shippers to cut many miles off the route from the Pennsylvania coal fields, down the Delaware, around Cape May, and up along the (occasionally treacherous) Atlantic Ocean coast to New York City.

Hudson River: The Hudson River is a 315 mi river that flows from north to south primarily through eastern New York in the United States.  The river originates in the Adirondack Mountains of Upstate New York, flows through the Hudson Valley, and eventually drains into the Atlantic Ocean, between New York City and Jersey City.  The river serves as a political boundary between the states of New Jersey and New York, and further north between New York counties.  The lower half of the river is a tidal estuary occupying the Hudson Fjord, an inlet which formed during the most recent period of North American glaciation, estimated at 26,000 to 13,300 years ago.  Tidal waters influence the Hudson's flow from as far north as Troy.

Mendocino Ridge AVA: The Mendocino Ridge AVA is a coastal, cool climate and high altitude American Viticultural Area located entirely within the coastal zone of Mendocino County, California.  The boundaries of the AVA encompass the coastal ridges adjacent to the Pacific Ocean that reach inland toward the Anderson Valley.  Roughly 36 miles of the southernmost portion of the Mendocino Coast make up the western boundary of the AVA, with the Sonoma County line as the southern boundary, the Navarro River as the northern boundary and Anderson Valley as the inland boundary running northwest-southeast.  The Mendocino Ridge AVA “is essentially a northern extension of the true Sonoma Coast viticultural area.”  However, the Mendocino Ridge AVA designation is unique in that it is limited by elevation, reserved only for vineyards at or above 1200 feet.  This is why the Mendocino Ridge AVA has been nicknamed “Islands in the Sky®,” because the vineyards sitting at 1200 feet or higher are often perched above thick fog moving inland from the Pacific Ocean blanketing the coast and the valleys between the ridge tops, making the tips of the mountains look like islands protruding from a sea of fog.  In this overlapping, “[t]he Mendocino Ridge AVA floats above the Anderson Valley and Mendocino appellations.”  Mendocino Ridge is the only non-contiguous AVA in the United States; all others are contiguous landmasses with all vineyards inside the boundaries designated as part of the AVA, whereas Mendocino Ridge in comparison only includes the higher altitude growing sites.  “There are 262,400 acres (410 square miles, 36 miles long from north to south) within the outer boundaries of the Mendocino Ridge viticultural area, but the actual viticultural area encompasses only 87,466 acres which lie above 1,200 feet elevation.  Of these 87,466 acres, approximately 1,500 to 2,000 acres (2% of the total acreage) of the ridge tops are suitable for vineyards.  The side-slopes are very steep (often above 70%) and covered with timber, making them unfit for planting”.  Estimates of planted acres range from 233 to 410, which accounts for about 0.3% of the total area.  These planted acres are scattered among 16 remote vineyards.

Supporting paragraphs: Geography of New York City Hudson River
Answer: 315