Yep, I think the answer to the original question pretty much comes down to:
-a 'mosto' in the most traditional or regular bars. Mmmm!
-a San Francisco cocktail at the discotheques.
-a refreshing 'horchata' for the most unique Spanish choice.
-an even more refreshing good old 'granizado de limón' (there are many more flavors nowadays) in the 'cafeterías'. Mmmmm!
-a glass of 'sidra'(cider) if you decide you don't mind a little alcohol after all. You can find the homemade kind at certain Basque or 'asturianas' eateries. Mmmmm!
-a little 'gazpacho' if you're not only thirsty but also a little hungry (served with ice cubes). :p
-a 'café con hielo' if you need to wake up after partying the night before....
-a 'clara', which is a mix of beer(make it non-alcoholic) and 'gaseosa'. Mmmm!
-a 'tinto de verano' in the summer, or whenever really. (This is very Spanish). It's a mix of 'gaseosa' and some red wine, it could be just a little little twist in your case
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