Sheep wandering over American city, wonderful old place (7)
I believe the answer is:
ephesus
'city wonderful old place' is the definition.
I can't judge whether this defines the answer.
'sheep wandering over american' is the wordplay.
'wandering' indicates an anagram.
'over' is a charade indicator (letters next to each other) (in a down clue, some letters go over others).
'american' becomes 'US' (United States).
'sheep' with letters rearranged gives 'ephes'.
'ephes'+'us'='EPHESUS'
Can you help me to learn more?
(Other definitions for ephesus that I've seen before include "Ancient Med. city" , "City with temple of Artemis" , "Ancient city of Lydia" , "Comedy of Errors setting" , "Ancient port in Turkey" .)