Ardashir I founded both the city and the administrative district sometime around 224 AD, the year he overthrew the Parthian king Artabanus V and established the Sasanian Empire. Archaeological evidence confirms the city predates the decisive battle -- Ardashir was building his capital even before he had won his throne. The circular plan was deliberate: a statement of cosmic order, royal authority, and engineering ambition. The inner compound, where the royal court lived and governed, occupied a circle 450 meters in radius at the city's heart. From this center, Ardashir ruled one of the four great administrative divisions of Pars, alongside Shapur-Khwarrah, Istakhr, and Darabgerd. A fifth division, Arrajan, would not be added until the early sixth century under Kavadh I.

Ardashir I built more than walls and government buildings. At the center of Gor he raised the Terbal, a tower whose spiral design would later be echoed by the Great Mosque of Samarra in Iraq. Scholars still debate its purpose -- observatory, fire altar, royal symbol -- but its uniqueness in Iranian architecture is beyond question. He also constructed a Zoroastrian fire temple in the city, one that the 10th-century Arab historian al-Masudi reportedly visited centuries later and found still standing. Fire temples defined the district. In the early fifth century, the powerful minister Mihr Narseh -- a native of Abruwan, one of Ardashir-Khwarrah's subdistricts -- founded four villages, each with its own fire temple. He built a fifth in his hometown, spending 30,000 dirhams on its construction according to an inscription the geographer Estakhri read when he visited in the 10th century.

Mihr Narseh left his mark on Ardashir-Khwarrah in stone and mortar. He served as wuzurg framadar -- chief minister -- under multiple Sasanian kings, and he used his wealth to build infrastructure that would outlast empires. A bridge he commissioned in Gor carried an inscription that reads like a prayer and a request: "This bridge was built by order of Mihr-Narseh, wuzurg framadar, for his soul's sake and at his own expense. Whoever has come on this road let him give a blessing to Mihr-Narseh and his sons for that he thus bridged this crossing." The words survived long enough for scholars to record them. By the time they were written, Gor had already hosted a Christian diocese, established sometime before 540 -- a sign of the religious diversity that complicated the Sasanian heartland.

In 650 AD, the last Sasanian king Yazdegerd III arrived in Gor hoping to organize resistance against the Arab armies sweeping across Persia. The city that had birthed his dynasty four centuries earlier seemed like the right place to make a stand. But news arrived that Istakhr, another great city of Pars, had already fallen. Yazdegerd fled east to Kirman. The Arabs quickly seized Gor, the port city of Siraf, and the rest of Pars. The circular walls, the fire temples, the bridge with its carved plea for blessings -- all passed to new rulers. The district that once carried the name "Glory of Ardashir" would be renamed, reorganized, absorbed. But the city's circular footprint endured in the landscape, and the ruins of the Terbal still rise from the plain.

Today the site of ancient Gor lies near the modern city of Firuzabad, whose name preserves the Sasanian renaming of the city to "Peroz" -- meaning victorious -- after Ardashir's defeat of the Parthians. The circular outline of the ancient city remains visible from the air, its geometry unmistakable against the surrounding farmland. Firuzabad and its Sasanian sites were inscribed as a UNESCO World Heritage Site in 2018, as part of the Sassanid Archaeological Landscape of Fars Region. The ruins speak of an empire that lasted over four centuries and stretched from Mesopotamia to Central Asia, but that began here, in a circle drawn on a plain, with a spiral tower at its center and four gates open to the world.