Route round town is near? Don't ask me!
I believe the answer is:
by-pass
'route' is the definition.
(I have seen 'Alternative route ' mean 'by-pass' so perhaps 'route' could also mean 'by-pass')
'round town is near? don't ask me' is the wordplay.
I cannot quite see how this works, but
'near?' could be 'by' (I've seen this in other clues) and 'by' is found in the answer.
The remaining letters 'pass' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for by-pass that I've seen before include "Ring-road" , "Out-flank" , "Way to avoid town etc" , "Road taking traffic around the edge of a town" , "Road built to avoid another" .)