Olesko Castle is an architectural monument of the XIV-XVII centuries, located near the village of Olesko, Bussky district, Lviv region, the oldest surviving castle in Western Ukraine.

The first settlement near the future Olesko Castle existed in 1700-600 BC. In the X-XII centuries, the ancient Russian settlement was located under the very castle hill.

Olesko Castle is one of the oldest buildings in Galicia. It was built at the crossroads of ancient trade routes from Wallachia and Vnegriya to Volhynia, and served as the key to this land. A study of the castle foundation showed that it was built immediately of stone, and there was no wooden fortress in its place. The walls were about 10 meters high and 2.5 meters thick.
The start time of the construction of the Olesko Castle is unknown. Possibly, the Olesko castle began to be built shortly after the devastation by the Mongol-Tatars in 1241 of the ancient Russian city of Plesnensk. According to researchers of the 19th century, unconfirmed by the current state of the study of sources, the castle was first mentioned in 1327; from this they concluded that it was built by one of the sons of the Galician-Volyn prince Prince Yuri Lvovich - Andrei or Leo.

The first reliable mention of the castle itself dates back to 1390, when Pope Boniface IX presented the Galician Catholic Archbishop with the Olesko castle and Tustan fortress with his bull.

The next reliable written evidence of the Olesko Castle dates back to 1431. That year, the Russian feudal lords of the Olesko land took the side of the Lithuanian prince Svidrigail and raised a rebellion against the Polish-Lithuanian king Jogail. The defense of the Olesko Castle was led by Ivashko Preslovich from Rohatyn. In 1432 Jogaila's troops took possession of the castle.
In 1441, the Polish king Vladislav III Varnenchik handed over the castle and the entire Oleska land to Jan from Senna - to defend the Russian lands from the Tatars. Large Tatar hordes passed through the lands of the Olesko district and approached the castle in 1142, 1452, 1507, 1512, 1519, 1575, 1629. In 1519, the owner of the castle Fryderyk Herburt died in a battle with the Tatars near Sokal, and another owner of the Olesko castle, Stanislav Danilovich, died in Tatar captivity in 1636.

In 1481, Peter Oleski (son of Jan from Senna) built a church near the castle. In 1546, the borders between the Grand Duchy of Lithuania and the Kingdom of Poland were demarcated. From the documents accompanying the demarcation, it is known that the Oleska land included the modern Brodovsky district, as well as part of the Bussky district of the Lviv region and the Lopatinsky district of the Ternopil region.

At the beginning of the 17th century, Mikhail Khmel, the father of Bohdan Khmelnitsky, served at the court of the Russian magnate Ivan Danilovich, who owned the castle.
On August 17, 1629, during a raid on the outskirts of the castle of the Crimean Tatars, the daughter of Ivan Danilovich in one of the rooms of the castle gave birth to the future king of the Commonwealth, Jan III Sobieski. Eleven years later, on July 31, 1640, in the Olesko Castle, the Polish magnate Yarema Vyshnevetsky (whom historians consider one of the saviors of Poland from the Khmelnytsky region) had a son, who also became the king of the Commonwealth - Mikhail Koribut Vyshnevetsky, the predecessor of Jan Sobieski on the Polish throne.

In 1646, Olesko was captured by the troops of Bogdan Khmelnitsky, and his allies, the Crimean Tatars, destroyed the city and the castle.
In 1682, Jan Sobessky bought the castle and since 1684 restoration and repairs have been carried out in it, the surrounding park has been equipped. In 1711, during the war between the contenders for the Polish throne, Russian troops lodged in the castle. In 1739, the Volyn governor Severin Zhevusky began the construction of the Capuchin monastery of St. Anthony near the Olesko castle. In 1806 and 1836 the castle survived great fires, in 1838 - a major earthquake, and fell into complete disrepair. Back in 1820, the Polish writer Julian Nemtsevich (who later described the castle in his works) wrote: “The castle is neglected ... the room where Sobieski was born is completely destroyed, full of garbage.” In 1891, restoration work was started again, and in 1898 a women's agricultural school was opened in the restored part of the building.
In 1939, the agricultural school and the Capuchin monastery were closed, the building of which is located at the foot of the castle hill. In the castle itself from October 1939 to mid-1940 there was a camp for Polish prisoners of war. During the years of occupation during the Great Patriotic War, the Nazis set up warehouses in the castle building. In 1951, the last big fire broke out in the castle. Since 1965, the staff of the Lviv Art Gallery began to equip the ruins of the castle. On December 21, 1975, a gallery branch was opened in the castle.