### Clue: Tricky navigation — a time one must leave city with a bridge (7)
### Answer: AVIGNON 
 ### Explanation: Definition: city with a bridge
An anagram ('tricky') of 'navig[ati]on', minus ('must leave') ATI ('a time one'), for the , where *on y danse* without worrying about traffic, as it ends in the middle of the Rhône.