Tunisian built on second peninsular peak (5,5)
I believe the answer is:
mount sinai
'peninsular peak' is the definition.
(mountain on the Sinai Peninsula)
'tunisian built on second' is the wordplay.
'built' indicates anagramming the letters.
'on' says to put letters next to each other.
'second' becomes 'mo' (both are short periods of time).
'tunisian' anagrammed gives 'untsinai'.
'untsinai' after 'mo' is 'MOUNT SINAI'.
(Other definitions for mount sinai that I've seen before include "Where laws were received" , "Where divine law handed out" .)