Diocletian's Palace, today ruins, is a great building in Split, which was made during the Roman times by the emperor Diocletian.
The building is one of the most famous and complete cultural and architectural features on the Croatian coast, and has been inscribed together with the part of historic city of Split built around the Palace on the UNESCO World Heritage List in 1979.

The purpose of Palace was place for retirement of the Roman Emperor Diocletian after his abdication of political life after 21 years of ruling the Roman Empire.

Begin of construction of Diocletian's Palace is not exactly determined. It is believed that work on the palace began in AD 295, and was finished 10 years later when emperor moved there, there are indications that some work was done while the Diocletian stayed in it. The basic material for Palace came from the immediate vicinity, while certain number of builders was native and the emperor brought some master workers from the east, probably Greece. The building as a whole had no direct role model in theretofore days of Roman building architecture. Its originality stems from the basic functions and position adjustments.

Diocletian's Palace was built as an intense structure, similar to a Roman military fortress. It faces the sea on its south side, and the walls were 170 to 200 meters long, and 20 meters high, enclosing an area of 38,000 square meters. The water supply to palace was substantial, fed by an aqueduct from nearby river spring. It is believed that palace and its surroundings were at times inhabited by 10,000 people.

Interesting fact is that Diocletian was first Roman Emperor to voluntarily remove himself from the power.

Today the Diocletian's Palace constitutes from the inner part of the city, full of squares, markets and shops, with an ancient cathedral built on the ground of the former palace.