Tried this in Brazil, it's called Swiss Limonade (Limonada Suiza) there. (Lime and Lemon are the same word)
Swiss, because the brand of condensed milk has the Swiss Alps on it.
When I make it at home - I blitz the limes first (peels and all), but not for too long. (Vitamix gang stand up).
Strain out the peel and skin, then take what's left, sugar, condensed milk, ice, and water.
It's damn good.
