A prisoner, caught, starts to actually go up a mountain (9)

I believe the answer is:

aconcagua

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'actually go up a mountain' is the definition.
I can't judge whether this definition defines the answer.

'a prisoner caught starts to' is the wordplay.
'prisoner' becomes 'con' (abbreviation for 'convict').
'caught' becomes 'c' (cricket abbreviation).
'starts to' becomes 'agua' (I can't justify this - if you can you should give a lot more credence to this answer).
'a'+'con'+'c'+'agua'='ACONCAGUA'

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I've seen this clue in the Sydney Morning Herald.

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