Welcome to Liberty City - Where the American Dream goes to die
The game is set in fictional Liberty City, based on the real life city of New York. This will be the 5th time Liberty City has been the setting of a Grand Theft Auto game; Grand Theft Auto, Grand Theft Auto III, Grand Theft Auto Advance, Grand Theft Auto Liberty City Stories and now Grand Theft Auto IV. Players may also remember visiting a snowy Liberty City in one mission on GTA San Andreas. As you can see, Rockstar Games have a soft spot for their first real living and breathing city.
Dan Houser explains the reason for their choice in setting GTA IV in Liberty City.
What's It Look Like?
The new Liberty City is not a direct, block for block, replica, but it resembles a striking resemblance to New York City. It is set in modern day, somewhere around 2006 or 2007. The city has 4 of the 5 boroughs of New York and parts of New Jersey. Staten Island is not in the game because Rockstar believed it would not be fun there. Also, Alderney is the largest of the 5 boroughs. The statue of Liberty is in the game and you can go to it by swimming or by boat.
The Five Boroughs
Broker - Churches, hipsters and housing projects
Broker is Liberty City's version of Brooklyn. Niko begins his journey with his cousin Roman. Roman and Niko run a Taxi Depot there.
Dukes - Like the suburbs, only worse
Dukes is Liberty City's version of Queens. Located directly north of Broker, Dukes was the site of Liberty City's Worlds Far back in the 1960s. Dukes is also home to Francis International Airport.
Algonquin - Self-proclaimed center of everything
Algonquin is Liberty City's version of Manhattan. This has many historic sites and buildings such as Times Square and the Empire State Building. This most likely will be the second borough Niko visits.
Bohan - Ripe for re-development
Bohan is Liberty City's version of The Bronx. Located in the north-east corner of Liberty City Bohan is undergoing a renaissance of a sort, all thanks to local resident Manny Escuela.
Alderney - Industrial wasteland meets suburban hell
Alderney is Liberty City's version of part of New Jersey. Not much is known on this borough, but it is said to be the largest borrough of GTA IV. Make sense, considering it is New Jersey, and not a borough like Queens or Manhattan.
Size of Liberty City
There has been much speculation about how large Liberty City is. Magazine articles originally stated it was smaller than San Andreas, now some say it is slightly bigger. Rockstar Games have seemingly said the game is not as big in terms of land mass as San Andreas, however everything is much more detailed, and there'll be no wasted open spaces like the desert.
This is from Game Informer in May 2007: