The Zrinski castle is a cultural monument of the "first category". In 1651 Petar Zrinski had its castle built in Brod na Kupi, probably on the foundations of an earlier castle built by the Frankopan family in the 15th century. In order to ensure better use of the natural resources, Petar Zrinski moved the administrative and judicial authorities from their earlier seats in the Vinodolski area (Hreljin, Bribir, Ledenice) to Brod na Kupi. Today the Zrinski castle is a simple three-storey stone building with a pyramidal roof. It appears that the third storey was originally made of wood. On the ground floor, the original arrangement of rooms has been preserved, while the layout of the chambers on the first and second floors has been changed by subsequent reconstructions. An underground passage leads from the ground floor to the Kupica river and the nearby cave. This interesting building once combined the fortifying and housing functions, which makes it particularly valuable. The Zrinski castle is finaly becoming the heritage and forestry museum with several thematic floors devoted to the goranian tradition of life and basic historical facts.