Książ Castle is a castle in northern Wałbrzych in Lower Silesian Voivodeship, Poland. The largest castle in the region of Silesia, it is the third-largest in Poland behind Malbork Castle and Wawel Castle. It lies within Książ Landscape Park, a protected area located in the Sudetes and Sudeten Foreland. The castle overlooks the gorge of the Pełcznica river and is one of Wałbrzych's main tourist attractions.

Wałbrzych is a city located in the Lower Silesian Voivodeship, in southwestern Poland. From 1975–1998 it was the capital of Wałbrzych Voivodeship; it is now the seat of Wałbrzych County. Wałbrzych lies approximately 70 kilometres (43 mi) southwest of the voivodeship capital Wrocław and about 30 kilometres from the Czech border. Wałbrzych has the status of municipality. Its administrative borders encompass an area of 85 km2 (33 sq mi) with 110,000 inhabitants, making it the second-largest city in the voivodeship and the 33rd largest in the country.