Importance of land surrounding ancient city (7)
I believe the answer is:
stature
'importance' is the definition.
(thesaurus)
'land surrounding ancient city' is the wordplay.
'land' becomes 'state' ('state' can be a synonym of 'land'**).
'surrounding' means one lot of letters goes inside another.
'ancient city' becomes 'ur'.
'state' enclosing 'ur' is 'STATURE'.
'of' is the link.
(Other definitions for stature that I've seen before include "Height, calibre" , "Body height or high reputation" , "Size or standing" , "High level of respect" , "Height - prestige" .)