Does anyone know the translation or name of cranberries?

I have tried several places and they are all trying to sell me blueberries, another place had what looked like cranberries but she said they were grosellas, which in my dictionary are currants.

This could be an expensive mistake at 5.95 for a  3 ouce tub, especially as I need 12 ozs of the damned things.

The Spanish obviously dont have cranberry sauce, either freshly made or out of a jar, as it's proving a nightmare to find.

Jools