The TV show Castle takes place in New York City and, as with most communities, the city has developed terminology, references, and nicknames unique to it. For those who do not live in New York City or have never traveled there, here is a list of New York References to help viewers understand what the cast means.
New York City is divided into 5 boroughs (sometimes the city is even referred to as The Five Boroughs): Manhattan, Brooklyn, Queens, The Bronx, and Staten Island. Located at the mouth of the Hudson River, which forms the city's western border with New Jersey, much of it encompasses three islands: Staten Island in the south, Manhattan Island in the north, and long Island in the east.
Central Park is located on Manhattan Island. Most streets and avenues are named with numbers (72nd Street, 3rd Avenue), but streets run east-west and avenues run north-south. The well-known avenues Park Avenue and Broadway run north-south on Manhattan Island with Central Park located in between them. Another oft-mentioned avenue is Lexington Avenue, which runs north-south on Manhattan Island one block east of Park Avenue. The name is often shortened just to "Lex", especially when referring to an address (the corner of 54th and Lex).
The Lincoln Tunnel crosses the Hudson River and connects Manhattan Island and the area of Weehawken, New Jersey. The Holland Tunnel runs underneath the Hudson River and connects the southern part of Manhattan Island to Jersey City, New Jersey.