Kuusisto Castle was a medieval episcopal castle on an island of Kuusisto in Kaarina

Kaarina

Kaarina is a small city and municipality of Finland.It is located in the Finland Proper region and is a neighbouring town of Turku, which is the capital of Finland Proper, therefore Kaarina is a part of the Greater Turku region. The municipality has a population of and covers an area of of...

, Finland

Finland

Finland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...

, near Turku

Turku

Turku is a city situated on the southwest coast of Finland at the mouth of the Aura River. It is located in the region of Finland Proper. It is believed that Turku came into existence during the end of the 13th century which makes it the oldest city in Finland...

. The castle was probably built in the early 14th century, although the site seems to have been bishop's residence already in the 1290s.

The castle was ordered to be demolished during the Protestant Reformation

Protestant Reformation

The Protestant Reformation was a 16th-century split within Western Christianity initiated by Martin Luther, John Calvin and other early Protestants. The efforts of the self-described "reformers", who objected to the doctrines, rituals and ecclesiastical structure of the Roman Catholic Church, led...

 in 1528 by the king Gustav I of Sweden

Gustav I of Sweden

Gustav I of Sweden, born Gustav Eriksson of the Vasa noble family and later known simply as Gustav Vasa , was King of Sweden from 1523 until his death....

. Excavation and reconstruction work on the remaining ruins began in 1891.