Once upon a time yacht and bike needed to travel (4,2,3,3)
I believe the answer is:
back in the day
'once upon a time' is the definition.
(both can mean at a certain point in history)
'yacht and bike needed to travel' is the wordplay.
'needed' means one lot of letters go next to another.
'to travel' is an anagram indicator (I've seen 'travelled' mean this).
'yacht'+'and'+'bike'='yachtandbike'
'yachtandbike' anagrammed gives 'BACK IN THE DAY'.
(Other definitions for back in the day that I've seen before include "Like worker returning home from night shift" , "At some earlier time" , "years ago?" .)