The Gate of All Nations, also known as the Gate of Xerxes, is located in the ruins of the ancient city of Persepolis, Iran.
The construction of the Stairs of All Nations and the Gate of All Nations was ordered by the Achaemenid king Xerxes I, the successor of the founder of Persepolis, Darius I the Great.
Wikipedia https://en.wikipedia.org/wiki/Gate_of_All_Nations
Address Iran
Coordinates 29°56'10.25" N 52°53'20.681" E