Only twelve kilometers from Persepolis, the ancient necropolis of Naqsh-e Rustam would be worth the trip even without that proximity. There are carvings here that date to 1000 BCE in addition to the four tombs of Achaemenid Kings, including Darius the Great and Xerxes. The tomb of Xerxes is not visible above, but is perpendicular to these three and just to the right.
The tomb of Darius the Great can be identified by the inscriptions on either side of the entrance. In addition there are incredible carvings depicting historical scenes; especially the one to the lower left which shows the triumph of Shapur I over the Roman emperors Valerian and Philip the Arab.
The unusual head gear on the man above led local people to believe he depicted Rustam, hero of the Persian epic Shahmaneh. However, the carving precedes the epic by almost two millenia, dating to 1000 BCE, seven centuries prior to Persepolis.
Naqsh-e Rustam was a revelation to me. Those who are lucky enough to visit Persepolis should absolutely add it to their itinerary.