Man blocks view in main route (3,4)
I believe the answer is:
sea lane
'main route' is the definition.
'sea lane' can be an answer for 'route' (thesaurus). I am unsure of the 'main' bit.
'man blocks view' is the wordplay.
'man' becomes 'alan' ().
'blocks' is an insertion indicator (the inside letters form a 'blockage').
'view' becomes 'see' (synonyms).
'alan' put within 'see' is 'SEA LANE'.
'in' is the link.
Can you help me to learn more?
(Another definition for sea lane that I've seen is " marine passage".)