The oldest relief at Naqsh-e-Rostam dates back to c. 1000 BC. Though it is severely damaged, it depicts a faint image of a man with unusual head-gear, and is thought to be Elamite in origin. The depiction is part of a larger mural, most of which was removed at the command of Bahram II.
The rock tombs at Naqsh-e-Rostam are definitely worth visiting as part of your trip to Persepolis. Hewn out of a cliff high above the ground, the four tombs are believed to be those of Darius II, Artaxerxes I, Darius I and Xerxes I (from left to right as you look at the cliff) although historians are still debating this. The tombs of the later Artaxerxes above Persepolis were modelled on these. The reliefs above the openings to the funerary chambers are similar to those at Persepolis, with the king standing on thrones supported by figures representing the subject nations below.
The seven Sassanian stone reliefs cut into the cliff depict scenes of imperial conquests and royal ceremonies; there are detailed descriptions in front of the tombs and reliefs.
Facing the cliff is the Bun Khanak (Central Home). This was long thought to be an
Achaemenid fire temple, but scholars now argue that it might have been a treasury. The walls are marked with inscriptions cataloguing later Sassanian victories.