Hard day Inland Revenue turned up for capital (6)
I believe the answer is:
riyadh
'capital' is the definition.
(Riyadh is an example)
'hard day inland revenue turned up' is the wordplay.
'hard' becomes 'h'.
'inland revenue' becomes 'ir'.
'turned up' is a reversal indicator.
'h'+'day'+'ir'='hdayir'
'hdayir' back-to-front is 'RIYADH'.
'for' is the link.
(Other definitions for riyadh that I've seen before include "Arab capital" , "Capital city of Saudi Arabia" , "Capital of Saud Arabia" , "Saudi Arabian city" , "Middle Eastern capital" .)