City's endless church district (5)
I believe the answer is:
paris
'city's' is the definition.
(Paris is an example)
'endless church district' is the wordplay.
'endless' means to remove the last letter.
'church district' becomes 'parish' (area associated with a church).
'parish' with its final letter taken off is 'PARIS'.
(Other definitions for paris that I've seen before include "foreign city" , "European capital -- Trojan prince" , "French city" , "Prince who abducted Helen, starting a long war (see 8)" , "I spar (anag)" .)