Some grandpas cottaging in a racy English town? (5)
I believe the answer is:
ascot
'a racy english town?' is the definition.
(town with a race course)
'some grandpas cottaging in' is the wordplay.
'some' indicates a hidden word (some of the parts of the word are used).
'ASCOT' is hidden within 'grandpas cottaging in'.
(Other definitions for ascot that I've seen before include "Berkshire racecourse - coast (anag)" , "Royal race meeting venue" , "course without any fences!" , "Horse-racing venue" , "Society race meeting" .)