There is a place called Paseo del Buen Pastor in Nueva Cordoba where people congregate to drink mate in the evenings. I'm not exactly sure what the building is, but there are a ton of shops inside... so maybe like a mall? Anyway, there is a water show starting at 5pm (7pm or 9pm), and it lasts about 10 min accompanied by music and lights. It's fun to watch for newcomers, but I'm sure it gets old for the people that live here :)
We brought along all the necessities to make mate; a thermos with hot water, sugar and of course the yerba. It's the coolest thing to look around at a couple hundred people (I'm only guessing here) and most everyone is carrying a thermos and drinking mate while they watch the show.
P.S. You can see the cathedral peeking from behind!!!!