Tough training venue (4,4)
I believe the answer is:
boot camp
'tough training venue' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for boot camp that I've seen before include "where terrier potentially goes" , "Harsh (US) military training establishment" , "correctional facility" , "US training centre for military recruits" , "Centre for juvenile offenders" .)