Island area or cape — climbing country (7)
I believe the answer is:
croatia
'country' is the definition.
(Croatia is an example)
'island area or cape climbing' is the wordplay.
'island' becomes 'ait' (I've seen this before).
'area' becomes 'a' (maths abbreviation).
'cape' becomes 'c' (abbreviation used on maps).
'climbing' says the letters should be written backwards (in a down clue, letters climb up).
'ait'+'a'+'or'+'c'='aitaorc'
'aitaorc' reversed gives 'CROATIA'.
(Other definitions for croatia that I've seen before include "East European country" , "Split country?" , "Balkan republic, capital Zagreb" , "Land in South-East Europe" , "From small country" .)