The Subway System aka "El Subte"
As a believer in the get out and about philosophy, I recommend that you get outside of the trendy central areas. A very useful and reliable resource is the "10 viajes" tarjeta which will set you back AR$7-00. Very handy for getting around the city, and be availed of alongside buses and taxis. For examlple its the best way the the Alto Palermo centre from the centro, as the station stops directly below. The centre also has a good food hall. Tarjetas can be bought at stations directly.
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