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It is geografically contained inside the province of Buenos Aires, but it is politically autonomous. Its coordinates are 34º 36' S, 58º 26' W.
The city extends on a plain covering 19.4 kilometers (12 miles) from north to south and 17.9 kilometers (11 miles) from east to west. Approximately three million people live in its 202 square kilometers (78.3 sq miles).
Together with its metropolitan area, it one of the ten most populated urban centers in the world.
Despite the constitutional claim of federalism, all the country activity is highly concentrated in this single city.
The city receives tourists from all the world constantly, so you can expect good services and a wide range of options.
The local phone code is 11. Long distance prefix: 0, international prefix: 00.
The international flights arrive to the Ezeiza airport, located in the suburban area named Gran Buenos Aires, about 40-60 minutes from downtown by highway. This airport provides taxis, private cars (remises), buses and minibuses. Public transportation not available from here.
Aeropuerto Internacional Ministro Pistarini
There are long distance services, but they are mostly for national use.
Theorethically, you can go to Buenos Aires from any of the neighbouring countries by car, but it is far away from most of the borders. It is only common to travel here from Uruguay and southern Brasil.
There are international bus services covering the neighboring countries. They all arrive to the Retiro bus station, very near to downtown.
There are daily journeys to and from Uruguay, two companies provide this service.
Buquebus - Puerto Madero terminal
Ferrytour - Dársena Norte terminal
From the official city site:
The City is an important destination for the maritime and fluvial cruisers industry of South America. The Benito Quinquela Martín Passenger Terminal, a few blocks away from downtown, at Ramón Castillo street between Avenida de los Inmigrantes and Mayor Luisioni street, has a surface of 7,100 square meters, a boarding room for 1,000 passengers and baggage facilities with capacity for 2,500 suitcases. In addition, it provides tourist information, handicrafts shops, snack bars; and Migration, Customs, Interpol and Prefectura (Coast Guard) Offices.
There are a good deal of railways connecting the suburban area in a star shape. The quality of the service ranges from good to very bad, depending of the line. Ask before using them at nighttime.
The main railway hubs are: Retiro, Constitución, Once and F. Lacroze, which are terminal stations used as a place for passenger transfer between railways, buses and metro. The fares are very cheap.
If you are interested in buying goods, you have a lot of shops in the downtown area, and many shopping centers, but beware, you can get much cheaper goods if you walk around the city. There are many artisans' fairs, most notably the Recoleta fair located in the Francia park, near Recoleta cemetery (which is an excellent place for photography).
From and to the rest of the country, travellers get to the Jorge Newbery airport, 10 minutes away from downtown area. You can take a taxi from here, but there also are public transportation available.
Aeroparque Jorge Newbery
There are national railways, but they are scarce. The terminal stations are the same from suburban transportation.
There are four main highways entering the city, those permit fast communication with the huge suburban area and access to the national routes. As with the trains, the most important routes are centered in Buenos Aires, so you will have no problem driving to and from the rest of the country.
Heading to Rosario city, you can travel by highway all the way (north access highway, then route 9), from here you can keep going to the north by a good route (Panamericana), or turn right about 150km from Buenos Aires and go to the Mesopotamia region.
To the west, you can drive to the Cuyo region using the north access highway, then the route 8.
Going out with the west access highway, you can follow by routes 7 and 5, heading to the west and southwest, respectively. For visiting western Patagonia, the route 5 is a good choice.
There are very good services parting from Retiro bus station, covering the whole country. By buying the most expensiev tickets, you can get very comfortable seats and on board meals.
Terminal de Omnibus de la Ciudad de Buenos Aires