See Wesley at regular intervals (3)
I believe the answer is:
ely
'see' is the definition.
(see is a place with a cathedral - e.g. Ely)
'wesley at regular intervals' is the wordplay.
'at regular intervals' means one should take alternating letters.
The alternate letters of 'wesley' are 'ELY'.
(Other definitions for ely that I've seen before include "Cambs. city" , "Cathedral city in Cambridgeshire" , "English cathedral city" , "Fenland city" , "Diocese in Eastern England" .)