Cool northern watering-hole (3)
I believe the answer is:
inn
'watering-hole' is the definition.
(I've seen this before)
'cool northern' is the wordplay.
'cool' becomes 'in' (I've seen this in other clues).
'northern' becomes 'n' (abbreviation e.g. N. Ireland).
'in'+'n'='INN'
(Other definitions for inn that I've seen before include "Tavern with lodgings" , "Small hotel or country pub" , "European river" , "Hotel with lodging for travellers" , "Jamaica, for one" .)