Diocletian's Palace

The city of Split grew up inside a Roman emperor's retirement home. This is not a metaphor or an architectural analogy — it is a literal description of what happened. When Diocletian, Emperor of Rome, abdicated in 305 CE and retired to the Dalmatian coast of his homeland, he moved into a rectangular palace-fortress he had spent a decade building near the provincial capital of Salona. After the fall of the Western Roman Empire and the destruction of Salona by Avars and Slavs in 614 CE, the palace's remaining walls offered the best available shelter, and several thousand refugees moved in. They built houses against the walls, subdivided the imperial apartments, converted the mausoleum into a church, and turned the garrison barracks into living quarters. The Roman palace became a city. Today, Split's entire old town — the restaurants, shops, apartments, and hotels where roughly three thousand people live and several million visit each year — occupies the footprint of Diocletian's original retirement residence. The palace is not a ruin. It is still a building, still inhabited, still in daily use. What makes it unique in the world of Roman archaeology is not the quality of its preservation but the continuity of its occupation.

Diocletian was born around 244 CE near Salona — the son of a freedman from Dalmatia, who rose through the Roman military ranks to become Emperor. His reign (284–305 CE) involved one of the most significant administrative reorganisations in Roman history: the establishment of the Tetrarchy, the division of the empire into eastern and western administrative units, the reform of the tax system and the military, and the Great Persecution of Christians (303–311 CE) — the most systematic Roman attempt to suppress Christianity before Constantine's conversion. He is also the only Roman emperor to voluntarily abdicate and live out his days in retirement. When colleagues begged him to return to power during a crisis, he reportedly said that if they could see the cabbages he was growing in his Dalmatian garden, they would understand why he preferred retirement.

The palace he retired to was built between 295 and 305 CE, following the basic design of a Roman legionary fortress — a rectangle approximately 215 by 180 metres, with walls reaching 25 metres in height, four named gates (Porta Aurea to the north, Porta Argentea to the east, Porta Ferrea to the west, Porta Aenea to the south opening to the sea), and an internal division between the northern garrison half and the southern imperial residential half. The distinction between palace and fortress is, by design, blurred: Diocletian understood that retirement in a period of political instability required defensible architecture.

The southern half contained the imperial apartments, the Peristyle (colonnaded courtyard serving as the formal entrance to the imperial quarters), the domed Vestibule (the anteroom to the private apartments), a ceremonial dining hall, and Diocletian's Mausoleum — an octagonal structure on a rectangular podium where he intended to be buried. The mausoleum became, with the deepest possible historical irony, the Cathedral of Saint Domnius: a Christian saint whom Diocletian had executed in 304 CE during the Great Persecution. The cathedral consecration happened in the 7th century, roughly when the refugee occupation of the palace began. Diocletian's personal burial monument became a Christian church dedicated to one of his victims, and the building still functions as Split's Roman Catholic cathedral. The original octagonal interior, Roman capitals, and stone relief portraits of Diocletian survive in the walls alongside 13th-century frescoes and the cathedral's medieval modifications.

Jupiter's Temple — a small hexastyle Corinthian temple in the northern corridor — became the cathedral's baptistry, retaining its coffered barrel vault and an Egyptian crocodile sculpture at its entrance. The Porta Aurea (Golden Gate) to the north remains the most complete of the four gates, with blind arcading and decorative niches. The Podrumi (underground halls) beneath the southern imperial apartments mirror the room layout of the apartments above and represent the most completely preserved section of Roman construction in the complex — accessible via a separate ticket and extensively used as a filming location, including for Game of Thrones.

Walking into the Peristyle — the central colonnaded court where café tables now stand between Diocletian's original columns — makes the continuous occupation of the palace physically immediate. The columns have medieval stonework patched between them. A Romanesque tower rises from the corner of the mausoleum. Medieval house facades cover Roman walls. At the northern end, the Vestibule is now open to the sky, its dome long since gone, ringed by the original blind arcading and used as a performance space in summer.

The Podrumi entry (approximately €12–15 adults) and individual monument tickets are the primary paid elements. The palace-city itself is free to enter at all hours. The guided walking tour (t54976, 4.9★, 5,280 reviews, from $17) is the highest-reviewed dedicated castle/palace tour product on this entire site — not a shared link with any other page — and provides the historical context that the physical experience of the palace-city benefits from significantly on a first visit. [Klis Fortress](/castles/croatia/klis-fortress), on the ridge above Split approximately eight kilometres inland, is the medieval counterpart — the Croatian royal fortress from which the region that Diocletian's palace made possible was controlled for centuries.