Puerto Madero District
I loved this area for its visual stimulation. It is the recently restored, latest official district, dock area of Buenos Aires. It is a combination of old brick warehouses and modern tower block buildings.

It has miles of pedestrian walkways along the banks of the river. Even at weekends there is plenty of space and the atmosphere is calm. You can see art exhibitions (currently statues of cows depicted in various ways, which I have seen somewhere else but can't remember where) and entertainers along the banks of the river, as well as eat in superb restaurants. We listened to a gaucho musical group and treated ourselves to a meal in what we were told was one of the best restaurants in BA - and it certainly lived up to its name. Not only was it incredibly cheap for an English person/couple, but the service was impeccable, the atmosphere very latin and the food 'maravilhoso' - a steak to die for (apologies to vegetarians!).

We also walked across the fabulous Puente de la Mujer (Women's Bridge) several times, which reminded me of the millennium bridge in Gateshead.