Tourists visit ancient Persian city of Persepolis in Iran

Tourists visit the ancient Persian city of Persepolis outside Shiraz, southern Iran, on March 27, 2019. Persepolis, a UNESCO world heritage site, was the capital of the Achaemenid Empire of Persia (550-330 BC). It was the king of kings, Darius I, who built an impressive palace complex inspired by Mesopotamian models. The importance and quality of the monumental ruins make it a unique archaeological site. (Xinhua/Ahmad Halabisaz)