Clue: Dicky Benaud is one going from Vienna to Belgrade (6)
Answer: DANUBE
Explanation: Definition: one going from Vienna to Belgrade
An anagram ('dicky') of 'Benaud'. It does not add much to the surface, but 'Dicky Benaud' could refer to Australian cricketer and commentator Richard Benaud, but, as far as I know, he used the diminutive Richie.