Walkway seen from Piraeus to Athens (4)
I believe the answer is:
stoa
'walkway' is the definition.
Both the definition and answer are singular nouns.
Maybe there's an association between them I don't understand?
'from piraeus to athens' is the wordplay.
'from' says the answer is hidden in the clue.
'STOA' is hidden in the letters of 'piraeus to athens'.
'seen' acts as a link.
Can you help me to learn more?
(Other definitions for stoa that I've seen before include "Roofed walkway with colonnades - oats (anag)" , "Colonnade, covered walkway" , "Philosophers' porch" , "Zeno's place" , "It sheltered Greeks walking" .)