The most significant castle in this area is Opeka. It is located within the Arboretum, one of the most valuable in Croatia, with a series of exotic and domicile species of plants. The castle was built in the 17th century by the Keglević family, and in the second half of the 18th century, the Drašković family rebuilt it as a single floor construction, in the shape of the letter U. After the Drašković family, the Bombelles family was in possession of the castle. When they came to Vinica in the 19th century, they rearranged and expanded the baroque castle and made a large park around it. They made a small wing in the north-western part of the castle and built a terrace and a tower on the main south-east facade. T
he facades of the inner yard were once open with arcade corridors that were later covered by walls. The park long the Opeka castle is rich in exotic plant species, and its design is due to Count Marko Bombelles. From his travels he brought different trees and shrubs, transforming the garden around the castle into the arboretum. Due to its exceptional artistic, dendrological, scientific, cultural-historical and other values, it has been protected as a monument of nature since 1947. In the walls of the castle, due to the damage of plaster, the spools buried in the walls are visible, of which a part of the antique stele with an inscription is highlighted.