Naqsh-e Rostam is an ancient Persian necropolis located about 12 km (7.5 mi) northwest of Persepolis in Iran. The site includes rock reliefs from the Achaemenid and Sassanid periods, and four tombs of Achaemenid kings. The oldest relief, dating from around 1000 BC, is thought to be Elamite in origin. The tombs carved into the rock, as seen from left to right in this panoramic photograph, are thought to belong to Darius II (423–404 BC), Artaxerxes I (465–424 BC), Darius I (522–486 BC), and Xerxes I (486–465 BC), respectively. An inscription on the facade of Darius I's tomb mentions his conquests and achievements. In the far left of the image is the Cube of Zoroaster, belonging to the Achaemenid era (5th century BC); its purpose is unclear. Inscriptions on its walls in three languages have been described as the "most important historical documents from the Sassanian era".Photograph credit: Diego Delso