Travelled to an ancient city with the editor (6)
I believe the answer is:
toured
'travelled' is the definition.
(touring is a kind of travelling)
'to an ancient city with the editor' is the wordplay.
'an ancient city' becomes 'ur' (ancient Sumerian city state).
'with' is a charade indicator (letters next to each other).
'the editor' becomes 'ed' (abbreviation).
'to'+'ur'+'ed'='TOURED'
(Other definitions for toured that I've seen before include "Went on sight-seeing expedition as to foreign parts" , "Went on holiday journey" , "Went on sight-seeing journey" .)