Found­ed by Dar­ius I in 518 B.C., Perse­po­lis was the cap­i­tal of the Achaemenid Empire. It was built on an immense half-arti­­fi­­cial, half-nat­ur­al ter­race, where the king of kings cre­at­ed an impres­sive palace com­plex inspired by Mesopotami­an mod­els. The impor­tance and qual­i­ty of the mon­u­men­tal ruins make it a unique archae­o­log­i­cal site.