This manor is an ensemble of an old and a new mansions and some outbuildings, which were constructed at the end of the eighteenth century and in the nineteenth century. This is one of the largest and the most beautiful manors in Lithuania. The complex is composed of 20 buildings located on 34 hectares. The old mansion is a classical building with some baroque style features. It was restored in 1981. Other buildings are typical examples of architectural history. The manor is surrounded by a park, where the River Mažupė flows.
From the middle of the eighteenth century, the manor of Joniškėlis belonged to property owners the family of Karpiai. In 1736, the King Augustus gave them the right to establish in this place a town with markets and three annual fairs. The mansion of Joniškėlis was recreated by its landlords in the beginning of the last quarter of the eighteenth century, after a fire of 1763. The manor and the town are directly connected by a visual system.
In 1940 the state took over the manor. Since 1967 until nowadays, the Joniškėlis Experimental Station of the Lithuanian Agricultural Research Institute resides here. Now there is a museum in the main building.