This section deals mainly with the architecture of the palace complex, and its buildings and embellishing reliefs. These date entirely from the Achaemenian period (518–331/30 B.C.) except for a few remnants of post-Achaemenid structures.

An inscription carved on the southern face of the Terrace proves that Darius the Great was the founder of Persepolis. Work was started about 518 B.C., although the tremendous task was not completed until about 100 years later by Artaxerxes I. Before any of the buildings could be erected, considerable work had to be done. This mainly involved cutting into an irregular and rocky mountainside in order to shape and raise the large platform and to fill the gaps and depressions with rubble.

According to tablets inscribed in Old Persian and Elamite found at Persepolis, it seems that Darius planned this impressive complex of palaces not only as the seat of government but also, and primarily, as a show place and a spectacular center for the receptions and festivals of the Achaemenian kings and their empire. Darius lived long enough to see only a small part of his plans executed. His brilliant and grandiose ideas were taken up and followed by his son and successor Xerxes, who, according to an excavated foundation inscription, said: “When my father Darius went (away from) the throne, I by the grace of Ahuramazda became king on my father’s throne. After I became king…what had been done by my father, that I also (did), and other works I added.”4 Actually, the Persepolis we know is mostly the work of Xerxes.

In dealing with the Persepolis platform, we have to understand that the northern part of the Terrace, consisting mainly of the Audience Hall of the Apadana, the Throne Hall, and the Gate of Xerxes, represented the official section of the Persepolis complex, accessible to a restricted public. The other part held the Palaces of Darius and Xerxes, the Harem, the Council Hall, and such. Following is a brief enumeration of the buildings, and their most outstanding features, that constitute the Terrace complex.