From 1276 to 1326, the cathedral of the Bishops of Lubusz stood there, later converted into a Marian sanctuary which existed until 1551. A number of archaeological surveys were conducted in Kępa Targacz. During the last excavation in 2018, a section of the filled-up moat was discovered which used to encircle the Bishops’ residence. The cache is located under a commemorative stone dedicated to the history of this place.