PETRA
'(<a href="http://www.j-archive.com/media/2011-11-14_J_28.wmv">Alex presents the clue from Petra, Jordan.</a>)  The approach to Petra is though a narrow cleft which in 312 B.C. helped it withstand a siege by the army of Antigonus of these people; he was an heir to Alexander the Great'
the Macedonians