Five on the beer in valley (4)
I believe the answer is:
vale
'valley' is the definition.
(I know that valley can be written as vale)
'five on the beer' is the wordplay.
'five' becomes 'V' (Roman numeral).
'on' means one lot of letters go next to another.
'the beer' becomes 'ale' (type of beer).
'v'+'ale'='VALE'
'in' is the link.
(Other definitions for vale that I've seen before include "Glen; goodbye!" , "Trough between ridges" , "Cheers" , "Maida -, N. London area; farewell (archaic)" , "'''Sweet ... of Avoca, how calm could I rest'' (Moore) (4)'" .)