It's high to climb - bet you turn back! (4)
I believe the answer is:
etna
'turn back' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Perhaps there's an association between them I don't understand?
'it's high to climb bet' is the wordplay.
'it' becomes 'e' ('e' can mean 'electronic' which is similar to 'IT').
'high' says to take the initial letters (I've seen 'highest of' mean this (top letter - down clues only)).
'climb bet' becomes 'na' (I can't justify this - if you can you should give a lot more credence to this answer).
The initial letter of 'to' is 't'.
'e'+'t'+'na'='ETNA'
'you' acts as a link.
Can you help me to learn more?
(Other definitions for etna that I've seen before include "Italian volcano" , "Volcano in Italy" , "Volcano; reverse of stake" , "Dangerous peak" , "Italian smoker" .)