Książ (pronounced: Ksyonsh [ˈkɕɔ̃ʂ], Polish: Zamek Książ, German: Fürstenstein) is the largest castle in the Silesia region, located in northern Wałbrzych in Lower Silesian Voivodeship, Poland. It lies within Książ Landscape Park, a protected area located in the Wałbrzyski Foothills. The castle overlooks the gorge of the Pełcznica river and is one of the Wałbrzych's main tourist attractions.