Odescalchi Castle, located in the western part of the fortified town of Ilok, is actually the partitioned medieval palace of Nikola Ilok, Croatian ban and king of Bosnia. It was built in the first half of the 15th century and is the most important residential-representative building in medieval Slavonia and Srijem. In the first half of the 16th century, Ilok was conquered by the Turks, and after the expulsion of the Turks, the Austrian Emperor Leopold I donated the castle to Livio Odescalchi in 1697, and the castle remained a summer residence until 1945.
The Palace of Nikola Iločki was built in the transitional Gothic-Renaissance style as a two-story fortified city citadel of a square monastic floor plan with an inner courtyard, auxiliary rooms, a representative knight's hall with vaults, an emporium and King Nikola's living quarters. During the Turkish rule, the palace was destroyed and neglected, at the end of the 17th century, the northern wing and all the rooms inside the fort were demolished. At the beginning of the 18th century, the Odescalchi princes began to rebuild the castle: the square floor plan was changed, the castle was baroqueized, and an arcaded portico built with brick, which is typical of Roman architectural culture, was added to the courtyard facade of the south wing on all three floors.
Today, the castle is a two-story, three-wing building with a U-shaped floor plan, open to the Danube, whose walls, foundations and vaults are built of bricks, while the ceilings and roof are of wooden construction, and the covering is made of pepper-tiles.
Extensive conservation-restoration, geomechanical and structural research carried out at the Odescalchi castle and preceded the renovation works. They include the static rehabilitation of the building, whose load-bearing structure has settled due to the action of water, the restoration of the entire roof covering and sheet metal, the restoration and reconstruction of the destroyed parts in accordance with the rules of the conservation and restoration profession, the rehabilitation of the facade and interior, and the decoration and adaptation of the interior itself.
