Cube of Zoroaster, Naqsh-e Rustam. View of the 5th Century BC Ka'ba-ye Zartosht (Cube of Zoroaster) at Naqsh-e Rustam, Iran. Naqsh-e Rustam is an ancient necropolis (cemetery) dating from around 1000 BC. This tower-like structure was built during the Achaemenid Empire (the world's largest ancient empire), which was founded in the 6th century BC by Cyrus the Great and lasted until it's collapse in 330 BC, under the leadership of Alexander the Great. The Cube is thought to have been a fire altar or eternal flame memorial to the emperors whose tombs lie a few metres away.