Discussed tower that's worth a look! (6)
I believe the answer is:
eyeful
'a look' is the definition.
(eyeful is a kind of look)
'discussed tower' is the wordplay.
'discussed' indicates a 'sounds like' (homophone) clue.
'tower' becomes 'eiffel' (Eiffel Tower is an example).
'eiffel' is a homophone of 'EYEFUL'.
'that's worth' acts as a link.
(Other definitions for eyeful that I've seen before include "Long steady look at something" , "As much as can be taken in by a look" , "Does a pupil contribute to this" , "Attractive sight" , "Fascinating sight" .)